Europe endorses Brexit deal and urges UK MPs to back it

European Union leaders endorsed a hard-fought Brexit deal with Britain on Thursday, but Prime Minister Boris Johnson faces an uphill battle getting it through the British parliament.

"It looks like we are very close to the final stretch," EU Council President Donald Tusk told after the other 27 leaders approved the accord.

But despite optimism from Boris, British opposition parties and some of the prime minister's own allies in the House of Commons were quick to warn they would not support it when it goes to a vote in a special sitting on Saturday.

If the deal is defeated, the prime minister is legally obliged to ask EU leaders to postpone Brexit for a third time -- breaking his vow to lead Britain out on October 31.

European Commission President Jean-Claude Juncker warned such a rejection would create an "extremely complicated situation", while Tusk said that if it happened he would consult member states on how to respond.