Britain's opposition Labour Party will back a call for a second referendum on Brexit, its leader Jeremy Corbyn will tell his MPs.
Parliament is due to debate and vote on Wednesday on the next steps in Britain's tortuous departure from the European Union on Brexit, and MPs are expected to put down proposals, or amendments, including at least one that would demand that the exit deal is put to a public vote.
"We are committed to also putting forward or supporting an amendment in favour of a public vote to prevent a damaging Tory (Conservative) Brexit being forced on the country," Corbyn will tell a meeting of his Labour MPs later on Monday, according to extracts provided by his office.
The party will also support a bid by Labour MP Yvette Cooper to give parliament the legal power to force May to seek an extension to the Article 50 negotiating period beyond the exit date currently set down in law - March 29.
Corbyn has been under pressure for some time to support a second referendum. Last week, eight referendum-supporting MPs quit the party, in part owing to frustration over his failure to back another vote.
The prospect of holding a second vote poses a dilemma for Corbyn; while many of the party's members and supporters fervently back a so-called People's Vote, others simply want Britain to leave the EU as soon as possible.
Labour said it would also put forward an amendment calling on the government to adopt its Brexit proposals, including a permanent customs union with the EU and close alignment with the bloc's single market.