British Prime Minister Boris Johnson speaks to the media in New York on September 24, 2019, on the sidelines of the United Nations General Assembly.

U.K. Prime Minister Boris Johnson has been prevented from holding a key vote on the Brexit withdrawal deal he recently agreed with Brussels.

The U.K. government was keen to have a "meaningful vote" on Monday, but this was rejected by House Speaker John Bercow as it's not parliamentary convention to repeatedly ask the same questions to politicians.

In outlining his decision, Bercow said there had been no change in either substance or circumstance since Johnson relinquished a first attempt to have a vote on his Brexit deal over the weekend.

The speaker said any attempt to have the vote today would be "repetitive and disorderly." Reuters data show that sterling slipped slightly to $1.2962 after the statement.

Bercow told the house that to move Brexit forward the U.K. government would be legitimate in its aims by introducing the legislation needed for Brexit, rather than having another "yes or no" vote.

The speaker added that the government would still have time to achieve Brexit by October 31.