A British one pound sterling coin. (File photo: AFP)

Britain has "paused" production of a commemorative coin to mark its exit from the European Union, which looks set to be delayed next week for the third time.

It is not known how many of the 50-pence coins had already been minted, nor their fate.

"We have paused production of the Brexit coin, and will take a final decision in due course," a Treasury ministry statement said late Friday.

The coin was inscribed with the Brexit deadline of October 31, and the words "peace, prosperity and friendship with all nations".

Business Minister Kwasi Kwarteng denied it was a "foolish" decision to start production before the date was confirmed.

"I think it was a very sincere aim of the British government to leave on October 31. I think it is sad if we don't leave on that date," he told BBC radio on Saturday.

Prime Minister Boris Johnson was required by law to ask EU leaders last weekend to delay Brexit after MPs refused to back the divorce deal he struck with Brussels.

The Conservative leader had previously said he would rather "die in a ditch" than see Britain's 46-year-old membership of the European Union continue past October 31.

The bloc's leaders have agreed in principle to a delay but have yet to decide for how long.