House of Commons Speaker John Bercow has ruled out another vote on Theresa May's Brexit withdrawal agreement if the motion is substantially the same as last time.
Speaker Bercow told the House of Commons: "If the Government wishes to bring forward a new proposition that is neither the same nor substantially the same as that disposed of by the House on March 12, this would be entirely in order.
"What the government cannot legitimately do is resubmit to the House the same proposition - or substantially the same proposition - as that of last week, which was rejected by 149 votes.
"This ruling should not be regarded as my last word on the subject. It is simply meant to indicate the test which the government must meet in order for me to rule that a third meaningful vote can legitimately be held in this parliamentary session."
Mr Bercow said last week's second meaningful vote "did not fall foul of the convention about matters having already been decided" because there were a number of legal changes to the deal, as well as the publication of three new documents.
But he said because it has been "strongly rumoured" the government plans to attempt to schedule a third and possibly a fourth vote, he was prompted to make today's statement "to signal what would be orderly and what would not".