Prime Minister Boris Johnson on Thursday announced what he said was a "great new deal" for Britain to leave the European Union, as leaders gathered in Brussels for talks.
"We've got a great new deal that takes back control," he wrote on Twitter, calling on lawmakers in London to approve the agreement at a rare Saturday sitting of Parliament.
A previous deal brokered by Johnson's predecessor, Theresa May, was rejected three times by Parliament, where the governing Conservative Party does not have a majority.
All eyes in London will now turn to whether Johnson, who has vowed to take Britain out of the EU by the end of the month, has enough support to push through the agreement in the House of Commons.
Northern Ireland's Democratic Unionist Party earlier said it could not support what was being proposed on customs and consent issues for the border with Ireland post-Brexit.
It also said there was a "lack of clarity" on sales tax. A DUP source said after Johnson's announcement that the party's position had not changed.
But Jeremy Corbyn, leader of the main opposition Labour Party, said the new deal should be rejected by MPs.
"It seems the prime minister has negotiated an even worse deal than Theresa May," he said in a statement, referring to a previous accord thrown out by MPs in November last year.
The proposals were "putting food safety at risk" and would open up Britain's cherished free state healthcare system to "takeover by private US corporations", he added.
"This sell-out deal won’t bring the country together and should be rejected," the veteran socialist said.
There was also opposition from the smaller opposition Liberal Democrats, which has said it would not honour the 2016 referendum result to leave the EU if it came to power.
"The fight to stop Brexit is far from over," Lib Dem leader Jo Swinson said, assessing Johnson's deal would have an adverse effect on the British economy, public services and environment.
"When this deal comes to Parliament, we will use every possible opportunity to give the public a People's Vote on the Brexit deal that includes the option to remain in the European Union," she added.
French President Emmanuel Macron welcomed the Brexit agreement struck between the EU and London, and suggested it could be approved by sceptical British lawmakers.
At a meeting of centrist leaders ahead of an EU summit in Brussels, Macron said he was "reasonably confident it can be ratified by a vote of the British Parliament".
The EU's chief negotiator Michel Barnier on Thursday hailed the last-minute deal.
"We have reached an agreement that is fair and reasonable and corresponds to our principles," Barnier told reporters, but urged caution as the deal must still pass through the British Parliament – which has rejected a Brexit deal three times before.
Negotiators in Brussels and London this week have gone from optimism to dismay and back again, with the pound twitching at every murmur. It rallied on news of the deal, touching US$1.2990 before paring gains.
In a revised political declaration, the two sides pledged to:
- establish a wide-ranging free trade agreement
- reach a deal on services that goes beyond WTO levels
- agree equivalence for financial services firms
- allow free movement of capital
- establish visa-free travel for short-term visits
- commit to a level playing field, with common high standards in state aid, competition, welfare, tax, and environmental matters.
Now, the many predictions about the costs or benefits of Brexit may be put to the test. At the very least, businesses and travelers will be spared the inevitable disruption that would have been triggered by Britain crashing out without a deal. For both sides, the agreement is a chance to move their political agendas on and to start focusing on their future trading relationship.
EU chief Brexit negotiator Michel Barnier told reporters in Brussels that he believes the deal can be ratified by the end of October. He called it a “fair and reasonable basis for an orderly withdrawal” by the UK.
In a nod to the painful wrangling of the past three years, he also compared getting the deal done to climbing a mountain.