Former British prime minister Tony Blair says Britain should hold a second referendum to bring “closure” to the chaotic Brexit process, and he believes the chances of such a vote taking place are now greater than 50 per cent.

With just over nine weeks till Britain is due to leave the European Union, there is still no deal on the terms and parliament last week crushingly defeated the plan that Prime Minister Theresa May negotiated.

“I think if you have another referendum it really will bring closure. People like myself accept if the country votes to leave again, that’s it,” said Blair, who opposes leaving the EU.

“But I think if you leave without going back to the people, with this mess and in these circumstances, there will be even greater division.”

Blair, who served as prime minister from 1997 to 2007, said Britain could not leave the EU unless it knew where it was heading.

If that meant applying to push back the March 29 Brexit date, then Britain should apply for that, he added.

“The idea that we can tumble out of the European Union without a deal, I mean this would be completely irresponsible and I’m sure that parliament won’t allow it,” he said.

Meanwhile, an Irish newspaper has claimed that secret plans are being drawn up to deploy Irish police to the border with Northern Ireland in the event of a Brexit deal.

The Irish Independent says about 600 officers could be required to man the estimated 300 border crossings along the 500 kilometre frontier.

Police on both sides of the border have warned that customs posts could be a target for the small number of militant groups still active in British-run Northern Ireland in the event that Brexit takes place.