Top oil executives are testifying before Congress amid accusations their companies misled the public about climate change
Democrat lawmakers say the industry spent decades denying its products' role in global warming
ExxonMobil, BP, Chevron and Shell bosses all deny approving any climate disinformation campaigns
The hearings open a year of investigations into energy giants, Democrats say
They also come days before world leaders gather in Glasgow for the UN's COP26 climate conference
World leaders will be pressed in Glasgow on their plans to cut greenhouse gas emissions and thereby reduce warming
It's not just top oil executives we'll be hearing from today.
Republicans have invited Neal Crabtree, a welder who lost his job after President Biden revoked a permit for the Keystone XL oil pipeline. He will testify to the panel.
They say he's an example of how Biden's climate agenda is costing Americans jobs.
We're hearing opening statements from the oil executives and lobbying chiefs now.
Here's a reminder of who we are going to hear from today:
At the heart of today’s hearing is the alleged role of fossil fuel firms in downplaying the scientific consensus on climate change.
The science itself isn’t up for discussion.
We know that climate change is being driven by humans burning oil, gas and coal.
When these fossil fuels burn, they release greenhouse gases. These gases trap the sun's heat and cause the planet's temperature to rise.
The world is now about 1.2C warmer than it was in the 19th Century.
The rise in temperatures has had devastating consequences - including stronger storms, bigger wildfires and the loss of habitats.
Here’s a really simple explainer of what climate change is.
Image source, ReutersExxonMobil CEO Darren Woods (file photo)
The first oil executive to testify will be Darren Woods, the CEO of ExxonMobil, who is appearing by video link.
After taking the oath, Woods makes an opening statement.
He tells the committee that ExxonMobil "has long recognised climate change is real and poses serious risks". But he says there is no simple solution.
The firm is committed to cutting emissions, he says, while making sure it meets the world's energy needs.
Ralph Norman, a Republican from South Carolina, is denouncing the hearing.
"Democrats are focused on destroying the oil industry," he warns.
Norman says "the American people are being abandoned" by the climate actions of the Biden administration, which he calls "overly ambitious and unrealistic".
"Now we're begging OPEC to make more oil and make it more affordable," he notes, criticising the cancellation of pipeline deals and oil and gas leases.
"The people of South Carolina did not send me to Washington to bankrupt the country," says Norman.
Democratic Committee Chairman Ro Khanna urges the oil executives to "spare us the spin" and "speak from the heart".
He says the executives can either own up to their firms' role in promoting climate disinformation, or "sit there, in front of the American public, and lie under oath".
He accuses the companies of trying to "deny and deceive" their past role in driving climate change.
The House Oversight Committee's top Republican says the hearing is misguided.
Ranking member James Comer asks why Democrats are not talking about inflation, high gas prices and other problems the Biden administration is facing.
He slams the hearing as "partisan theatre for primetime news" and "a distraction".
Comer asserts today's testimony is only happening because Democrats "watched a deceptively reported and edited video of an Exxon lobbyist".
Chairwoman Carolyn Maloney has opened proceedings, saying she hopes today's hearing "represents a turning point for big oil".
"I hope that today the executives own up the industry's central role in this crisis and commit to the changes we need," she says.
"After four decades of deception and delay, it is time for the fossil fuel industry to finally change its ways."
The hearing is the start of a year's worth of investigations into whether oil firms misled Americans about their role in climate change.
The hearing has kicked off, with some members in the committee room and others appearing by Zoom. Chairwoman Carolyn Maloney has called it a "historic" event.
You can watch the proceedings in our stream at the top of this page.
Image source, EVNSamira Hussain
New York business correspondent
Democrats are trying to compare this hearing to the blistering testimony by Big Tobacco in the 1990s, when executives admitted to the harmful impacts of smoking cigarettes.
A photo of the so-called Seven Dwarfs, leaders of the largest tobacco companies testifying to Congress was emblazoned on the front pages of newspapers all over the US and around the world.
But this hearing will not likely have quite the same impact.
The oil execs are allowed to testify by video, which means it won’t have the same visual impact. And as with most things in Washington these days, the hearing will be very partisan.
Republicans have already said they will use the hearing to denounce the Biden administration’s climate change agenda.
There's a slight delay to the start of the hearing, but the committee's chair, Ro Khanna, is in his seat - and we're expecting proceedings to get under way very soon.
We'll bring you updates when the hearing starts.
Chris Morris
BBC Reality Check
This is a big moment.
It’s the first time senior oil and gas executives have appeared before Congress - under oath - to face accusations that the fossil fuel industry has spent decades waging a disinformation campaign, in order to cast doubt on the science of climate change.
Their critics compare this inquiry to the hearings on the tobacco industry in the 1990s.
Energy companies have denied lying to the public about the effects of climate change, but Democratic members of the Congressional Committee will be keen to make them sweat.
And the timing of this hearing, just a few days before the UN climate summit COP26 begins in Glasgow, is no accident.
It’s taking place when the climate is right at the top of the global political and media agenda.
Image source, ReutersShell says it wants to move towards renewables such as hydrogen
We're expecting the oil executives to focus on their current support for climate action.
All major oil companies have publicly supported the Paris climate deal countries agreed on how to tackle climate change.
BP, Chevron and Shell have also made “net zero” commitments - which means taking out as much greenhouse gases as they put in the atmosphere.
As they come under increasing pressure from investors, the firms say they want to shift from selling fossil fuels to renewables.
But environmentalists have accused them of "greenwashing", and say most of their focus is still overwhelmingly on extracting fossil fuels.
We're expecting the proceedings in Washington to kick off shortly, at around 10:30 local time (15:30BST).
You can watch a live video stream at the top of this page, and we'll be bringing you updates throughout.
Image source, Getty ImagesToday's hearing has been likened to the Big Tobacco hearing in the US Congress in 1994
Six oil industry leaders will take the stand at today's hearing.
They are:
Image source, Getty ImagesCongressman Ro Khanna
Today's hearing is taking place in the House Oversight and Reform subcommittee on the environment.
Lawmakers on the committee, particularly Democrats, will likely take advantage of their rare face time with Big Oil's top executives.
Leading the charge will be chairman of the subcommittee Ro Khanna, a Democrat who represents the Silicon Valley area.
"We cannot tackle the climate crisis unless we tackle the climate disinformation crisis," Khanna said, in a video posted to social media.
Outspoken progressive congresswoman Alexandria Ocasio-Cortez - a co-author of the "Green New Deal" proposal - also sits on the subcommittee.
Republicans have traditionally been more friendly to fossil fuel companies.
Pat Fallon of Texas - the top oil and gas producing state in the nation - and Yvette Herrell of fossil fuel-rich New Mexico are expected to bemoan the loss of American energy independence under the Biden administration.
Image source, Getty ImagesEnvironmentalists claim Exxon misled investors on the financial risks of climate change
We already have a sense of some of the accusations we can expect the House of Representatives Oversight Committee to press the executives on today:
All four oil giants say they are committed to reducing greenhouse gas emissions. ExxonMobil has previously denied that it hid scientific evidence and says it has supported climate science for over 40 years.
Read more: How the oil industry made us doubt climate change
Hello and welcome to our live coverage of today’s hearing in the US Congress.
Top executives from major US oil companies are about to testify before a congressional committee over accusations they misled the public over the reality of climate change.
This is the first time industry bosses will answer questions about climate change in Congress under oath.
Giving evidence (remotely) are the CEOs of Exxon, Chevron and BP America, the president of Shell and the heads of lobby firms the American Petroleum Institute and the US Chamber of Commerce.
The companies say they want to use the hearing to highlight their recent efforts to combat climate change.
We’ll bring you updates and analysis from our teams in Washington DC and London as the hearing unfolds.