A Brexit supporter wears a tie with pro-Brexit pins as she arrives for a "Leave Means Leave" rally in London, Britain January 17, 2019. REUTERS/Simon Dawson

LONDON (Reuters) - Britain’s opposition Labour Party is seeking to force Prime Minister Theresa May to rule out leaving the European Union without a deal and to give parliament a vote on the options to break a deadlock over the way forward.

May’s deal was roundly rejected by parliament last week and on Monday she set out a proposal to overcome the impasse by seeking further concessions from the EU on a plan to prevent customs checks on the Irish border.

Lawmakers will debate and vote on the next steps on Jan. 29, and ahead of that they can put forward amendments to the government’s plan, seeking to shape Britain’s exit from the bloc.

Labour’s amendment seeks to force the government to give parliament time to consider and vote on options to prevent Britain leaving on March 29 without an agreement. Among those options should be a permanent customs union with the EU and a second referendum on Brexit, the party said.

“The prime minister is both refusing to change her red lines or take the threat of a no deal exit off the table. MPs (members of parliament) must now act to break the deadlock,” Labour leader Jeremy Corbyn said in a statement.

“Our amendment will allow MPs to vote on options to end this Brexit deadlock and prevent the chaos of a no deal.”