Democrats have called the legislation a "moral monstrosity"
Politicians in the US House of Representatives have passed a controversial bill to repeal large sections of President Obama's signature healthcare legislation 'Obamacare'.
The vote passed by 217 votes to 213.
20 Republicans voted against the bill, alongside every single Democrat in the House.
As Republican lawmakers celebrated the result of the vote, a number of Democrats chanted 'na na na na, na na na na, hey hey hey, goodbye' - referencing their belief that the proposed law will see the rival party suffer in next year's mid-term election.
Although the bill is likely to undergo significant changes in the Senate, today's vote is the first step in fulfilling one of Donald Trump's main campaign pledges to replace his predecessor's signature achievement.
Speaking in the White House Rose Garden after the vote, President Trump claimed: "We suffered with Obamacare. I went through two years of campaigning, and no matter where I went people are suffering so badly with the ravages of Obamacare.
"I will say this - as far as I'm concerned, your premiums are going to start to coming. We're going to get this passed through the Senate - I feel so confident."
He added: "Make no mistake: this is a repeal & replace of Obamacare."
A previous attempt to pass the American Health Care Act - which has been dubbed 'Trumpcare' - marked a high-profile political failure for President Trump and House Speaker Paul Ryan in March after they were unable to muster up enough votes.
A series of revisions later won over many hard-line conservatives who previously opposed the bill.
In the process, however, Republican officials risked losing the support of more moderate representatives.
The new bill proposes a number of sweeping changes to existing US healthcare law - including a removal of a requirement that insurance companies cover 'essential health benefits', and the 'phasing out' of an expansion of the Medicaid social healthcare programme.
The New York Times reports that the push to pass the bill gathered fresh momentum on Wednesday after two Republican representatives - Fred Upton and Billy Long - secured an amendment that would provide $8 billion in federal funding to support insurance costs of people with pre-existing conditions.
The proposed legislation has drawn strong criticism from healthcare and patient advocate groups.
The American Medical Association said: "Proposed changes to the bill tinker at the edges without remedying the fundamental failing of the bill – that millions of Americans will lose their health insurance as a direct result of this proposal."
A full analysis of the revised bill has not taken place, but the Congressional Budget Office reported that the original version of the bill would lead to 24 million people losing their insurance coverage by 2026.
Republicans were able to afford to have 22 of their members vote against the bill - but in the end only 20 voted against the bill.
Campaigners on social media had been encouraging people opposed to the bill to phone up representatives' offices in a bid to persuade them to vote against the legislation.
Republicans are pushing ahead with Trumpcare.— Rep. Keith Ellison (@keithellison) May 4, 2017
I’m voting NO, of course, but I want to hear your voice.
Call my office. (202) 225-4755.
Despite the tight vote count, Republican officials had voiced optimism that they had the support to pass the bill.
House majority leader Kevin McCarthy told reporters yesterday: "We have enough votes. It’ll pass."
Democratic leader Nancy Pelosi slammed the legislation, saying: "House Republicans are going to tattoo this moral monstrosity to their foreheads, and the American people will hold them accountable."
The controversial legislation will now face an even tougher challenge in the Senate.
Senators are likely to significantly amend or remove sections of the draft legislation.
Speaking after today's vote, Senator Bernie Sanders said: "The bill that Republicans passed today is an absolute disaster. It really has nothing to do with health care. It has everything to do with an enormous shift of wealth from working people to the richest Americans.
"It would provide a $300 billion tax break to the top 2% and hundreds of billions more to the big drug and insurance companies that are ripping off the American people. Our job now is to rally millions of Americans against this disastrous bill to make sure that it does not pass the Senate."