John Bercow says parliamentary rules prevent a motion being brought back repeatedly for votes in the same session of Parliament. He says the government can't "resubmit to the House the same proposition or substantially the same proposition" that has already been rejected.
Bercow's statement complicates Prime Minister Theresa May's attempts to get her deal approved. Lawmakers rejected the deal in January and again last week. May has been holding talks with opponents in a bid to persuade them to back the bill at a third attempt this week.
Amid the gridlock, lawmakers voted last week to delay Brexit by at least three months.
British Prime Minister Theresa May's spokesman says there has been no breakthrough in talks on winning Parliament's support for the government's EU divorce deal — and there is just a day to shift opinion before Britain will have to seek a long delay to Brexit.
Spokesman James Slack says talks are continuing between the government and the Democratic Unionist Party, whose support is crucial.
May hopes to bring her twice-rejected Brexit deal back to Parliament this week for a third vote. But Slack says the government will only do that if there is "a realistic prospect of success."
May will have to make that judgment by the end of Tuesday. Wednesday is the last day a vote can be held before May heads to an EU summit where she will ask the bloc to delay Brexit.
If the deal has been approved, May will ask for a short "technical extension." If it is not, she will seek a much longer delay.
European Union foreign ministers are urging Prime Minister Theresa May to make clear Britain's position on leaving the bloc, as the Europeans weigh whether to approve an extension to the Brexit process.
Ahead of a Brexit-focused summit of EU leaders this week, the ministers implored May once again to set out clearly what she wants from her European partners, less than two weeks before the Brexit date.
German Foreign Minister Heiko Maas said Monday: "We have to know what the British want: How long, what is the reason supposed to be, how it should go, what is actually the aim of the extension?"
Belgium Foreign Minister Didier Reynders said: "We are not against an extension in Belgium, but the problem is, to do what?"
British Prime Minister Theresa May is making a last-minute push to win support for her European Union divorce deal, with attention focused on wooing Northern Ireland's Democratic Unionist Party.
The DUP's 10 lawmakers are pivotal to May's effort to overturn two overwhelming defeats in Parliament, because their support could influence hard-line members of May's Conservative Party. Opposition has focused on the so-called backstop, designed to ensure there is no hard border between Northern Ireland and the Republic of Ireland.
But May suffered a setback Monday when former Foreign Secretary Boris Johnson refused to support her deal.
Johnson used his column in the Daily Telegraph to say that further changes are needed to the backstop, claiming it left the U.K. vulnerable to "an indefinite means of blackmail" by Brussels.