UK's unity at stake

Sir John Major and Tony Blair yesterday warned that a vote to leave the EU would "jeopardise the unity" of the UK as they campaigned together in Northern Ireland.

They suggested a Leave vote may re-open Scotland's independence issue and put Northern Ireland's "future at risk" by threatening its current stability. But Northern Ireland Secretary Theresa Villiers said support for the peace process there was "rock solid".

She said it would be "highly irresponsible" to suggest otherwise. The DUP's deputy leader Nigel Dodds agreed, saying the ex-PMs' comments were "dangerous, destabilising and... should not be happening".

The former Conservative and Labour prime ministers, who were instrumental in the Northern Ireland peace process in the 1990s, hit the campaign trail there as Remain campaigners attempted to make the future of the UK a key question in the 23 June referendum on EU membership.

It was a message echoed by former US president Bill Clinton in an article for the New Statesman, who said he worried for Northern Ireland's "future prosperity and peace" if the UK votes to leave.

Meanwhile, Brexit campaigners accused the government of trying to rig the EU referendum and threatened legal action yesterday as former London mayor Boris Johnson squared up for the campaign's first TV debate.

British MPs yesterday approved emergency legislation to extend voter registration -- a move that has infuriated the "Leave" camp because many late requests have been from broadly pro-EU younger voters, reports AFP.

Arron Banks, co-chairman of the Leave.EU campaign, said it was "a clear attempt to rig the referendum or, at a bare minimum, to load the dice".

"It's a desperate attempt by the establishment to register as many likely Remain voters as possible. We are therefore considering all available legal options," he said. Conservative MP Bernard Jenkin said the vote to change electoral rules during the campaign was "on the cusp of legality".