LONDON (AP) — The chairman of Britain's Conservative Party is urging Parliament to back an unpopular withdrawal agreement as British and European Union officials seek a breakthrough on the Brexit impasse.

Brandon Lewis on Saturday warned recalcitrant lawmakers, including many in his own party, that if the government's withdrawal plan is voted down Tuesday it is possible Britain will end up staying in the EU.

"We need to win that vote," he told BBC.

There is no sign of progress in the crisis talks between Britain and the EU and no indication of a major shift in Parliament in favor of Prime Minister Theresa May's bill, which was soundly thrashed in January and remains largely unchanged.

May's hopes for passage depend on winning some concessions from the EU in the coming days.