We've just heard from Republican Tom McClintock, who says short of declaring war, impeachment is the most serious act that Congress can do.

He adds that it must never be used to settle political differences.

McClintock says lawmakers owe it to the country to get to the bottom of the allegations, which requires the House to invoke it's full investigatory powers and lay all of the facts out for the American people.

It's important to note that this debate is about an impeachment inquiry, not an impeachment.

An allegation from Republican lawmakers that continues to come up is that the White House has refused to cooperate with the investigation into President Biden.

Last month, a White House lawyer rejected requests from House Republicans to interview members of the Biden administration as well as Biden's family. The lawyer argued that the Republican-led investigation was not valid because the House had not authorised the probe.

Republican lawmakers have argued today that formalising the inquiry will help allow them more timely access to witnesses. "That's why we need this vote," Rep Jim Jordan said earlier.

A vote to formalise the inquiry is expected later today.

Erin Houchin of Indiana has brought up Hunter Biden's refusal to testify at a closed-door hearing with Republican lawmakers earlier today, and says he is "ignoring" his subpoena. Hunter said he would only testify in a public setting.

She claims the Biden administration has been "stonewalling" the investigation and is "trying to hide the truth".

• You can read more about Hunter Biden's reaction to his father's impeachment probe here.

Republican Ralph Norman says he's in full support of the impeachment inquiry, adding that it follows the bar set by Democrats during impeachment proceedings against Donald Trump in 2019.

"We're playing by the same rules the Democrats set," he says.

He says the Democrats thought this process was fair for Trump, and they should think it's fair for President Biden.

Bernd Debusmann Jr
Reporting from Capitol Hill

Democrats and Republicans have taken two very different approaches to the impeachment issue during the debate on the House floor - showing the stark divide in how the parties see the issues at play.

The Republicans, for their part, have repeated a litany of grievances and what they see as clear evidence of wrongdoing on the part of the Biden family.

They clearly see the evidence as compelling and hard to refute, and seem confident that a fair amount of the US public will agree with them.

Democrat speakers have so far sought to clearly make the point that they see the evidence as bogus or debunked.

They've also, notably, sought to tie the issue to former President Donald Trump and his continued influence over the Republican party.

His spectre looms large in the room, even if he isn't here. He has been, after all, the biggest and most prominent voice in US politics attacking the Biden family.

Many of his staunchest allies in the House are among the small group of Republican lawmakers still in the room.

Right-wing lawmaker Jim Jordan is now accusing the Biden family of corruption, claiming: "this is a story as old as the hills".

Like his Republican colleagues, Jordan accuses the White House of refusing to cooperate with their investigation, claiming they blocked testimony from Justice Department officials.

"That's why we need this vote," Jordan says, arguing it would allow for "timely participation" from officials investigators want to talk to.

Now we're hearing from Democrat Jamie Raskin.

He says the Biden impeachment investigation "isn't a whodunit, it's a what is it?"

"It's like an Agatha Christie novel, where the mystery is - what's the crime?" he adds.

He says after 11 months, no one can say what President Biden's crime was.

As Comer finishes his speech, Rep. Jim McGovern got up to rebut his points, saying he is taking the House down a "rabbit hole".

He brings up a placard with pictures showing ex-president Donald Trump at a rally set next to a photo from the 6 January Capital riots.

McGovern says Trump was a "wannabe dictator" who encouraged the mob to attack the Capital on 6 January 2021.

Trump has been a constant theme from Democrats so far in this debate.

Bernd Debusmann Jr
Reporting from Capitol Hill

So far, this House debate has been largely dry and procedural - but Massachusetts Democrat Jim McGovern has palpably changed the tone.

His remarks were heated and animated - clearly, he doesn't think he needs to be here, a sentiment that has been shared by many Democrats.

Meanwhile Republican James Comer unsurprisingly has quickly taken aim at the Biden family and what he termed their alleged "lies".

It's hard not to sense the irritation on the side of the room where the Democrats are sitting.

Maryland's Jamie Raskin - who has repeatedly called the impeachment issue a sham - was leaning back in his chair, shaking his head and occasionally chuckling at Comer.

Up next is James Comer, the chairman of the House Oversight Committee who is one of several lawmakers leading the impeachment inquiry.

He starts by claiming President Joe Biden has "repeatedly lied to the American people" about his "influence-peddling schemes".

He claimed the House impeachment investigation has revealed "how Joe Biden knew of, participated in and benefitted from his family cashing in on Biden name around the world".

He cites one instance in which one of Hunter Biden's associates said Hunter used to put his father, who was then vice president, on speaker phone during business meetings.

Republicans have led a months-long investigation into the president that has yet to uncover any concrete evidence of misconduct.

Democrat Jim McGovern is up now. He starts off by saying they are there for one reason, which is that "Donald Trump demanded that Republicans impeach, so they are going to impeach".

He says Republicans don't work for the American people, they work for Trump.

"This whole thing is an extreme political stunt," McGovern says.

"It has no creditability, no legitimacy and no integrity. It is a sideshow," he adds.

Image source, Reuters

Before the debate kicked off, US House Speaker Mike Johnson said he was confident that the impeachment resolution will pass in the House, which Republicans control by a narrow 221-213 margin.

Asked if the vote will have the support of all GOP members, he said: “I think it’s going to pass." He added that it is “called for and appropriate”.

CNN reports that he would not say if every member of the Republican conference will support it.

We've just finished hearing the rules of the debate, and it's Republican Rep. Tom Cole who's speaking first.

He calls today a "sad day for myself, the institution and the American people".

"My duty today is one that I do not relish," he adds.

He goes on to bash the White House for "stonewalling" House Republicans in their impeachment probe into President Biden.

He says three committees are nearing the end of their investigations into Biden.

The impeachment inquiry has now officially been raised in the House.

Reading clerk Tylease Alli is currently explaining how the debate will unfold.

She says the House will determine whether sufficient grounds exist to impeach the president.

Alli is still reading through a very long list of clauses which sets out how the debate will take place.

You can watch the debate by clicking the Play button at the top of the page.

Bernd Debusmann Jr
Reporting from Capitol Hill

The two men who have largely been driving the impeachment issue on the Republican side, Jim Jordan and James Comer, are still sitting next to each other and appear to be getting ready for what's ahead.

Notebooks are open across their laps, and Jordan is occasionally taking notes.

Florida Republican Byron Donalds, who is sitting in the row behind them across a narrow aisle, has occasionally walked over to speak to them.

Earlier this week, Donalds told Fox News that he believes the impeachment investigation will likely be finished in the next month or two, with impeachment articles drafted by the Spring.

There are currently 21 Republican Representatives on the floor, by my count, compared to 15 Democrats. We expect that people will trickle in and out.

Democrat Ted Lieu has now brought up the impeachment inquiry, saying Republicans can not explain what action President Biden took "that they thought was illegal or criminal".

Lieu says Republicans are focused on the wrong priorities.

Stay with us as we bring you more.

Bernd Debusmann Jr
Reporting from Capitol Hill

Debate over the Biden impeachment issue is going to begin after a series of one-minute speeches on a variety of matters - the current speakers, for example, are recognising constituents.

There are, however, signs of what's to come today. Across the room, I can see several Democrats gathered around in a huddle, some of them looking down at their phones.

Ted Lieu, a California Democrat, is standing with his arms crossed, occasionally turning to some of his Democratic colleagues to chat.

Jim Jordan - one of the most vocal opponents of the Biden administration in the House - has just entered the room and sat down next to James Comer.

Notably, Jordan is wearing a blazer - an uncommon occurrence for a man who has become well known for his shirt-and-tie look.

The last time I saw him wearing a jacket, he was running - unsuccessfully - to become Speaker of the House.

The House is in session and lawmakers are giving general speeches.

After these short speeches, we expect the debate into the Biden impeachment inquiry to start.

You can watch the live stream of the debate by pressing Play at the top of this page.

Bernd Debusmann Jr
Reporting from Capitol Hill

I've just entered the chamber of the House of Representatives, where lawmakers will soon be discussing the move to formalise the impeachment inquiry into Joe Biden.

It's so far almost completely empty. The only representative I've seen so far is Kentucky Republican James Comer, who walked across the room drinking from a plastic water bottle before throwing it in a rubbish bin.

He's now taken his seat and appears to be listening to a clip of himself discussing Hunter Biden from earlier today. It's loud and I can clearly hear it from the elevated gallery where I'm sitting.

The last time I was in this room was during the battle to Speaker of the House, a position that ultimately went to Mike Johnson.

There is none of that frenetic energy this time.

Image source, Getty Images

Ex-House Speaker Kevin McCarthy launched the inquiry in September claiming Republicans had unearthed a "culture of corruption" surrounding US President Joe Biden.

But at the inquiry's first hearing later that month, two of the party's own expert witnesses told lawmakers they did not believe there was enough evidence to warrant impeachment.

Since then, the House oversight committee has issued a flurry of legal summons, demanding testimony from several members of the president's family, including his son and his brother.

Hunter Biden, the president's son, was subpoenaed to appear for a closed-door testimony today. He arrived at the Capitol this morning and blasted the inquiry, said he would only testify in a public forum, then abruptly left.

Senior Republicans have also claimed the White House is rebuffing their information requests, withholding thousands of documents from the National Archives and blocking key witnesses from testifying.

A vote to formalise the inquiry would give them greater legal firepower to enforce subpoenas, depose witnesses and gather evidence.