We're now closing our live coverage of Kamala Harris choosing Tim Walz as her running mate on the Democratic presidential ticket.

Thank you for joining us.

You can read more about the day's news below:

Walz touts record and attacks Trump in first rally as VP pick

The ex-football coach and teacher - now Harris's VP pick

Trump and allies attack Walz as 'dangerously liberal'

Why Harris picked dark horse Walz for VP

Our writers for this page were Rachel Looker, Madeline Halpert, Anthony Zurcher, Nomia Iqbal, Nadine Yousif, Ana Faguy and Bernd Debusmann, Jr.

It has been edited by Brandon Livesay, Emily McGarvey, Laura Blasey, Christal Hayes, Phil McCausland, Gareth Evans and Caitlin Wilson.

The US constitution does not have much to say about the office of the vice-president - the job is mostly about being able to take over at a moment’s notice in the event the president is unable to continue his or her duties.

The vice-president also serves as president of the Senate, presiding over important sessions and casting tie-breaking votes if necessary.

The first vice-president, John Adams, famously complained about the position’s insignificance.

In the early days of the United States, presidents didn’t get to pick their own number twos - the runner-up in a presidential election automatically became vice-president.

The role has steadily gained more power since the mid-20th century, and many vice-presidents have played integral roles in their administrations since then.

Lyndon B Johnson and Gerald Ford found themselves suddenly presidents when John F Kennedy was killed and Richard Nixon resigned.

Dick Cheney significantly shaped the George W. Bush administration’s Iraq war policy.

Mike Pence was at the centre of the 6 January, 2021 Capitol riots as Trump supporters stormed the building in an effort to get him to overturn the 2020 election result.

And Joe Biden was once vice-president to Barack Obama.

Image source, Getty Images

The most recent poll from CBS, the BBC's US partner, shows Kamala Harris and Donald Trump in a tight race nationally.

Harris holds a one-point lead over former president Trump.

Across battleground states, the poll indicates that the pair are neck-and neck, where Trump held a five-point lead when Joe Biden remained in the race.

Trump still enjoys a small lead in a few states - Wisconsin, Georgia and North Carolina - but the race has tightened significantly since Biden bowed out and Harris became the Democratic nominee.

The poll released on Sunday suggests that Harris has energised the Democratic base, with young, black and female voters noting their renewed enthusiasm for the presidential election.

Tim Walz has just become the Democratic candidate for vice-president - but the Minnesota governor isn't actually a Democrat.

In Minnesota, Democrats are technically members of the Democratic-Farmer-Labor (DFL) Party.

As politics in the United States are overwhelmingly controlled by the two major parties - the Democrats and Republicans - the DFL is affiliated with the Democratic Party nationally, and espouses most or all of the same policy platforms.

The party was created in the 1940s, when the state's mainstream Democratic Party merged with the more progressive Farmer-Labor Party.

There is only one other similar situation in US politics - in North Dakota, Democrats are members of the Democratic-Nonpartisan League Party.

Nomia Iqbal
North America correspondent, reporting from Philadelphia

Image source, Nomia Iqbal / BBC

The crowd here at the rally in Pennsylvania lapped up Harris and Walz's appearance.

One voter here Brandon told me, "Today I donated to Kamala Harris for the first time", because "she will show up for us so I need to show up for her."

He admits he was unhappy with the way President Joe Biden was replaced on the Democratic ticket a few weeks ago - but says at the same time the party has now been given a new lease of life.

For many voters here the new duo’s campaign has clear messages which they think stand in stark contrast to their opponents'. They view Donald Trump as old and rambling and label his running mate JD Vance "weird" - an insult that was first coined by Walz.

Some also dismiss the idea that the 91 days until Election Day is too short a time span for Democrats to pull ahead in this race - and think this burst of excitement towards the end of the cycle is better, rather than people getting bored by a long and drawn-out campaign run.

Image source, Getty Images

We just saw Minnesota's First Lady Gwen Walz on stage in Philadelphia after her husband - newly minted vice-presidential candidate Tim Walz - spoke at his first rally with Democratic presidential nominee Kamala Harris.

Like her husband, Gwen Walz is also a former educator. She taught in public schools as well as prisons. Minnesota's first lady met Tim Walz in western Nebraska, where she started her teaching career.

They were wed in 1994 and have two children together, Hope and Gus.

Gwen Walz was born in Glencoe, Minnesota, where she and her three sisters were raised by their parents Val and Linn, who were educators and small business owners, according to her official bio.

Vice-President Kamala Harris and her running mate Tim Walz have just concluded their first appearance together after Harris, the Democratic nominee for president, announced that Walz, the Governor of Minnesota, will be her running mate.

If you're just joining our live coverage, here's what you've missed:

• Harris introduced Walz as her running mate to supporters for the first time at a rally in Philadelphia, Pennsylvania
• Both began their remarks by praising Josh Shapiro, the Democratic Governor of Pennsylvania and one of the top contenders for Harris's running mate pick, though the vice-president ultimately chose Walz
• Speaking to the crowd beforehand, Shapiro endorsed the Harris-Walz ticket, calling Walz an "outstanding governor" and a "great patriot"
• During her remarks, Harris touted Walz's record in public service, as well as his background as a high school teacher, a football coach and a servicemember in the US National Guard
• Walz said he "couldn't be prouder to be on this ticket"
• The new Democratic nominee for vice-president took aim at Donald Trump, saying the former president is "too busy serving himself" and warned that a second Trump term will mean an erosion of freedoms in the US
• Walz also mentioned his opponent JD Vance, saying "I cannot wait to debate the guy"

From dark horse candidate to vice-presidential pickpublished at 00:07 British Summer Time 7 August

00:07 BST 7 August

Anthony Zurcher
North America correspondent, in Philadelphia

Image source, Reuters

As they walked out onto the stage, Tim Walz turned to Kamala Harris and mouthed one word: “Wow”.

It spoke to the enthusiastic response from the Philadelphia crowd, but also reflected the incredible journey Walz has been on for the past week, from dark horse candidate to vice-presidential pick.

After that electric entrance, Walz got a first hand introduction to running-mate obligations - standing behind the presidential candidate and nodding and clapping as they deliver their stump speech.

Once it was Walz’s turn to talk, he also showed some of the Midwestern wit that moved him to the top of Harris’s vice-presidential list. After noting that violent rates went up under Donald Trump, he added - with a smile - “and that doesn’t even count the crimes he committed”.

He repeated his label of his vice-presidential opponent JD Vance as “weird”.

And on the topic of abortion, he said the government should follow a Midwestern golden rule: “Mind your own damn business”.

The capacity crowd at this 10,000 seat arena, which had been at a frenzied pitch for more than an hour, ate it up.

Now the two candidates hit the road, with 91 days left until election day. “That’s easy,” Walz said of the three-month home stretch. “We can sleep when we’re dead."

Walz finishes by saying that over the next 91 days on the campaign trail, he will "have vice-president Harris's back."

"And we will have yours," he tells the crowd.

His wife, Gwen, and Harris's husband Doug Emhoff then join the two on stage before they walk off together.

Walz hits out Republicans over women's healthcare and in vitro fertilization (IVF), saying when the party discusses freedom, "they mean freedom to invade your doctor's office".

He says he was raised to respect a person's healthcare choices, as it's a private matter. He notes the lengths it took for him and his wife to start their family and the fertility treatments they endured.

He says they waited and waited for good news and when they welcomed their daughter into the world, they named her Hope.

"When the vice president and I talk about freedom, we mean the freedom to make your own healthcare decisions."

Image source, Reuters

Walz says he wants the US to be "a place where we settle our political differences not through violence but with our votes".

What direction will this country go in? he asks, adding that "Donald Trump will for sure take us backwards".

He tells supporters not to believe Trump when he downplays Project 2025, adding that his opponent knows exactly what it entails.

He says Trump "won't fight for your family," and that he "will ban abortion".

Walz also mentions Trump's running mate JD Vance, saying "I can't wait to debate the guy".

For context: Project 2025 proposes, among other things, hugely expanding the powers of the US president, gutting federal services, restricting access to abortion and large tax cuts.

Governor, teacher, coach: Tim Walz makes his debutpublished at 23:47 British Summer Time 6 August

23:47 BST 6 August

Nomia Iqbal
North America correspondent, in Philadelphia

The Harris campaign is trying to shift the vibe and right now, it very much feels like a rock concert vibe.

You can hardly hear anyone speak amid all the cheering and clapping. People are waving signs, dancing and wearing glow in the dark wrist bands, chanting one of the new slogans of the Democratic ticket “No going Back”, in reference to Donald Trump.

From where I’m stood, I have a clear line of vision of both Harris and Walz. We are packed in with the rest of the media. And as Harris was speaking, Walz appeared very emotional at times, pursing his lips whilst clapping and tapping his heart.

We are told that their chemistry was one of a few reasons why she picked him in the end and you can tell she has a sense of pride as she lists his qualifications: governor, teacher, coach.

This rally is of course a gathering for the party faithful. Everyone here is reenergised by Harris and Walz but the fight with their Republican opponents now really begins.

In his speech, Walz takes a jab at the Republican presidential nominee Donald Trump, saying that "he sees the world differently".

"He doesn’t know the first thing about service - because he’s too busy serving himself," he says.

Image source, Getty Images

Walz tells supporters that he spent his early years living in Butte, Nebraska - a small town of 400 people "where community was a way of life".

"Growing up, I spent summers working on the family farm. My mom and dad taught us to show generosity toward your neighbours and to work for the common good," he says.

He also speaks about his dad serving in the Korean War, as well as his own service in the National Guard.

"For 24 years, I proudly wore the uniform of this nation," Walz says.

Walz says he "couldn't be prouder" to be Harris's running mate.

"Vice-President Harris has fought on the side of the American people," he says, from her first day as a prosecutor up to now.

"She took on predators and fraudsters, took down transnational gangs, stood up against powerful corporate interests, she’s never hesitated to reach across the aisle if it meant improving people’s lives," Walz says.

"She does it all with a sense of joy," he adds.

Walz now takes the mic after Harris introduces him as "the next vice president of the United States".

He is met with a rapturous applause from the crowd.

"Thank you Philadelphia," he says. "Thank you madame vice-president for putting your trust in me. But maybe more so, thank you for bringing back the joy."

He adds that he is thrilled to be part of this "incredible journey".

Walz also praises Pennsylvania governor Josh Shapiro as a "visionary leader".

Image source, Reuters

Harris says of her and Tim Walz: "We agree on many things."

One of them is strengthening the middle class, which she says will be her "defining goal" if she were to be voted in as president.

She speaks about Walz's time as governor of Minnesota, where he helped pass a law that ensures children in public schools have access to free breakfast and lunch.

Harris adds that Walz was "the first governor in the country to enshrine reproductive freedoms as a fundamental right" after Roe v Wade was overturned.

She also praises Walz's gun policy. She notes that he is a gun owner and a hunter who believes in "reasonable gun safety laws in America."

Kamala Harris says Tim Walz is a "proud product of a middle class family in rural Nebraska".

She mentions Walz's military service and his background as a school teacher, "long before he entered politics."

Harris says Walz taught social studies and served as the line-backer coach for his high school's football team.

"Tim Walz was the kind of teacher and mentor that every child in America dreams of having, and that every kid deserves."

"That is the kind of vice-president America deserves," she adds.

Harris is continuing her speech with some of the trademark lines that have come to define her campaign.

She highlights her experience as a prosecutor and says she "took on perpetrators of all kinds".

"So hear me when I say, I know Donald Trump's type."

She calls her campaign "the underdogs" but acknowledges the momentum since President Joe Biden bowed out of the race and she became the nominee.

"This campaign is not just a fight against Donald Trump. Our campaign is a fight for the future," she says amid cheers.

Harris lays out her vision for America's future, saying her campaign wants to fight for fundamental freedoms.

"I set out to find a partner to help build this brighter future," she says, introducing her running mate Tim Walz.

She calls Walz a "leader who will help unite our nation and move us forward... a fighter for the middle class" and a "patriot".

The crowd is chanting "Tim, Tim, Tim, Tim!"