LONDON (Reuters) - Theresa May's plan to govern with the support of a Northern Irish protestant party risks thrusting the province back into turmoil by convincing 'hard men' on both sides of the divide to return to violence, former Prime Minister John Major said.
May's botched election gamble forced her to seek a deal with the Democratic Unionist Party (DUP), increasing the influence of pro-British unionists who have struggled for years with Irish nationalists who want Northern Ireland to join a united Ireland.
One of the architects of the settlement that brought an end to three decades of violence in Northern Ireland, Major said he was concerned that May's reliance on the DUP could create the perception that London was no longer an honest broker.
"I am concerned about the deal. I am wary about it. I am dubious about it," Major, who served as prime minister from 1990 to 1997, told BBC radio.
Major warned that although Northern Ireland was a long way from returning to the violence that killed 3,600 people, he believed the peace process remained fragile nearly two decades after a U.S.-brokered 1998 peace agreement.
"We have seen in Northern Ireland over very many years that events always don't unwind as you expect them to unwind," he said. "We need to hope for the best but prepare for the worst.
"The last thing anybody wishes to see is one or other of the communities so aggrieved that the hard men, who are still there lurking in the corners of the communities, decide that they wish to return to some form of violence."
Major said London's impartial role in Northern Ireland remained a fundamental part of the peace process.
"The danger is that however much any government tries, they will not be seen to be impartial if they're locked into a parliamentary deal at Westminster with one of the Northern Ireland parties," he said.
Major said his list of concerns included how a post-Brexit Britain would resolve the issue of the Northern Ireland border with Ireland, the UK's only land border with the European Union.
Any hard border, he said, would be catastrophic.
Major said he sympathised with May and her need to shore up her position, but he urged her to consult more widely on her approach to Brexit, saying he thought the so-called hard Brexit was "increasingly unsustainable".
May met the DUP leader Arlene Foster on Tuesday to discuss a deal for support in parliament. Foster said discussions were going well.
Editing by Guy Faulconbridge