Just days after voting to leave the European Union, more than 1.5 million Britons and UK residents had signed a petition calling for a second vote, forcing lawmakers to at least consider a debate on the issue.

The petition on the British parliament website was posted before the June 23 referendum, saying the government should hold another plebiscite on EU membership if the support for Leave or Remain in a referendum is less than 60 per cent based on a turnout of under 75 per cent of electors.

The result on Thursday saw 52 per cent of voters back a British exit on a turnout of 72 per cent of eligible voters.

Since then, the petition - which only British citizens or UK residents have the right to sign - was proving so popular that by 1417 GMT on Saturday, 1,580,220 people had signed it with the number rising quickly.

It appeared to be rising at a rate of around 1,000 signatures a minute at one point.

Most of those who signed were based in areas where support for staying in the EU was strongest such as London, the website indicated.

Parliament has to consider a debate on any petition which attracts more than 100,000 signatures.

Prime Minister David Cameron, who said on Friday he would resign after leading the failed campaign to keep Britain in the EU, has previously said there would be no second referendum.-Reuters