May fails to win over her party before Brexit vote

LONDON, Mar 12 (Reuters): Britain's exit from the European Union hung in the balance on Tuesday after Prime Minister Theresa May's newly won assurances on her divorce deal failed to win over the main Brexit faction in her Conservative Party hours before a vote in parliament.

In a last-ditch bid to plot an orderly path out of the Brexit maze days before the United Kingdom is due to leave, May rushed to Strasbourg on Monday to agree legally binding assurances with European Commission President Jean-Claude Juncker.

But Attorney General Geoffrey Cox said in a written opinion the assurances left the legal risk of the United Kingdom being locked in the bloc's orbit after Brexit, the most controversial issue for Brexit-supporting lawmakers.

"The legal risk remains unchanged," Cox said. "However, the matter of law affecting withdrawal can only inform what is essentially a political decision that each of us must make."

Sterling fell as much as 2 cents on Cox's advice, which was seen as reducing the chance that May's deal will be approved by parliament. It was trading at $1.3092 at 1323 GMT.

British lawmakers, who on Jan. 15 voted 432-202 against May's deal, will vote at 1900 GMT. The main pro-Brexit faction in May's party, the European Research Group, said it did not recommend voting for her deal.

The main sticking point is the so-called Irish border backstop, an insurance policy aimed at avoiding controls on the border between the British province of Northern Ireland and EU-member Ireland after Brexit.

Brexit-supporting lawmakers expressed suspicion at the haste of May's last-minute assurances and suggested a delay to allow sufficient analysis of them and Cox's advice.