The UK's opposition Labour Party will back Remain if Britain holds a referendum on a Brexit deal negotiated by the Conservative government.
Labour leader Jeremy Corbyn changed his stance as he called for the next prime minister to put the deal to a public vote.
However, he did not go as far as outlining what Labour's position would be in the event of a General Election.
"Whoever becomes the new prime minister should have the confidence to put their deal, or no deal, back to the people in a public vote," he told party members in an email sent on Tuesday.
"In those circumstances, I want to make it clear that Labour would campaign for Remain against either no deal or a Tory deal that does not protect the economy and jobs."
He acknowledged the issue of Brexit “has been divisive in our communities and sometimes in our party too”. But he said the party was right over the past two years to have respected the result of the 2016 referendum.
“Labour set out a compromise plan to try to bring the country together based around a customs union, a strong single market relationship and protection of environmental regulations and rights at work. We continue to believe this is a sensible alternative that could bring the country together,” he said.
But the Labour Party has been under pressure since the Liberal Democrats, the third party in British politics, did exceedingly well in European Parliament elections on the basis of their pre-EU position.
Labour-affiliated trade unions on Monday agreed to support holding a new referendum on any divorce deal that the Conservative government strikes with the European Union.
The same position applies if the government seeks to take Britain out of the EU without any deal at all.
The unions play an influential role and their agreement will embolden the pro-European wing of the party.
Conservative Prime Minister Theresa May is stepping down this month after failing to get her divorce plan through parliament.
The two men vying to replace her, Boris Johnson and Jeremy Hunt, have both threatened to take Britain out of the EU with no deal on October 31.
However, the majority of members of parliament -- including Labour -- are against a "no deal" option, fearing the economic consequences.
Neither Hunt nor Johnson supports the idea of a second referendum.
If the political deadlock continues, many in Westminster believe a snap election is inevitable.