Former prime minister Sir John Major has warned against Brexit being dictated by the "tyranny of the majority", insisting that the views of Remain voters should be heard.
The ex-Conservative leader told guests at a private dinner that the 48% of people who voted to stay in the European Union should have their say on the terms of the deal for breaking away from Brussels.
Sir John said he accepted the UK would not remain a full member of the EU but hoped the Brexit deal would enable the country to stay as close as possible to the other 27 members and the single market, The Times reported.
He said Parliament, not the Government, should make the final decision on any new deal with the remaining members of the EU and added there was a "perfectly credible case" for a second referendum.
"I hear the argument that the 48% of people who voted to stay should have no say in what happens," he said.
"I find that very difficult to accept. The tyranny of the majority has never applied in a democracy and it should not apply in this particular democracy."
Sir John, in a speech and Q&A to mark the 100th anniversary of David Lloyd George becoming prime minister, hailed the single market as "the richest market mankind has ever seen" in his first intervention in the Brexit debate since the June 23 vote.
The former prime minister's time in Number 10 was marked by a series of bruising battles with his own MPs over Europe and his comments are likely to cause fresh anger among Eurosceptic Tories.
His comments come after his successor in Downing Street, Tony Blair, suggested the Brexit process could be halted.
The former Labour leader told the New Statesman: "It can be stopped if the British people decide that, having seen what it means, the pain gain cost-benefit analysis doesn't stack up."