Nigel Lawson, a UK finance minister under Margaret Thatcher who once favoured pegging the pound to a European currency, said on Thursday he would lead a campaign for Britain to exit the European Union as "an elder statesman".
Mr Lawson is the latest party grandee to join one side or the other in a debate over whether Britain should stay in the EU ahead of a referendum prime minister David Cameron has promised to stage by the end of 2017.
The referendum is set to divide Britain’s main political parties, with Mr Cameron widely expected to support continued membership in the EU but allow senior figures in his Conservative Party to campaign against it.
The debate is also likely to be contentious in the Republic, notably because of strong trade links with Britain and the Border with the North.
Mr Cameron says he will announce his final position only after negotiations with the EU to improve the terms of Britain’s membership. He personally favours Britain staying in a reformed EU, but would “not be heartbroken” to leave.
One of Mr Cameron’s goals in holding the referendum is to bury an issue that dogged his Conservative predecessors for decades. Mr Lawson’s appearance in the debate is a reminder of how deeply the party was split over Europe in the past. As finance minister from 1983 to 1989, he resigned after clashing with Mrs Thatcher over Britain joining the European Exchange Rate Mechanism.
Unanimity not forthcoming
He said on Thursday he was convinced Mr Cameron would not be able to achieve major concessions in his renegotiation with the European Union, because real change to EU rules requires unanimous support from the 28 member countries.
“I have been around a long time, I don’t make this judgment lightly, but all the evidence is that that unanimity is not going to be forthcoming,” the 83-year-old former politician told BBC radio.
He denied he was anti-European, saying he was talking to the radio presenter from “his home in France”, but said most of Britain did not want to stay in a bloc whose main goal was ever closer union and “a United States of Europe”.
His stance will bring him into opposition with other Conservative Party grandees, including Kenneth Clarke, another former finance minister, now vice-president of the European Movement in the United Kingdom campaigning to stay in the EU.
The debate over whether Britain should stay in the European Union is set to be fierce, with both sides well financed and well practised in arguments that have swirled since the country joined the European Economic Community in 1973.
Most opinion polls show a majority of Britons back staying in the EU, but the migrant crisis in Europe has made some warier than before of the bloc’s guarantee of free movement to citizens of all 28 member countries.
The election of leftist Jeremy Corbyn as leader of the main opposition Labour Party this month has raised new questions about the position of mainstream political parties.
Labour has traditionally supported EU membership. Mr Corbyn has been more sceptical than many in his party in the past, but after a week of policy confusion following his election finally committed to reforming the bloc from within.
With the mainstream parties still expected to support membership, the campaign to leave will be counting on establishment figures to step forward to gain credibility.
Mr Lawson has emerged in recent years as a prominent sceptic of science that blames human activity for climate change, a position that is seen as far from the main stream in Britain.
Opponents are also likely to criticise his record in office during the Thatcher years, a polarising period in Britain.
"Nigel Lawson is the chancellor with the worst record in history," said Liberal Democrat politician Richard Kemp on Twitter.