'WISHFUL THINKING'

Simon Coveney, foreign minister of Ireland, whose economy stands to suffer most from a 'no-deal' Brexit, said Britain had not offered any feasible way to keep the border open:

"What we are being asked to do here is to compromise on a solution that works, and to replace it with wishful thinking."

And Irish Prime Minister Leo Varadkar told May by phone that "the latest developments had reinforced the need for a backstop which is legally robust and workable in practice", an Irish government spokesman said.

European Commission President Jean-Claude Juncker said the chances of a 'no-deal' exit had increased, and currency traders also took that view as sterling traded around $1.3070, more than a cent down from its level before lawmakers voted on Tuesday.

EU sources said additional clarifications, statements or assurances on the backstop might be possible, short of reopening the agreement.

But May says she needs more - a legally binding change. She aims to get parliament's approval for a revised deal on Feb 13.

If that fails, parliament will vote on next steps on Feb 14.

That deadline ratchets up the pressure on dedicated Brexiteers in the Conservative Party who fear opponents will try to delay and ultimately thwart Britain's exit.

Both May's Conservatives and the main opposition Labour Party are formally committed to carrying out Brexit, but internally divided over how or even whether to do so.