Prime Minister Theresa May says she will not “give in” to those calling for a second referendum on Brexit.
Writing in the Sunday Telegraph, she says such a move would be a “betrayal of democracy” – and of the trust of the people who voted to leave the EU.
The People’s Vote, a cross-party group including some MPs, is calling for a public vote on the final Brexit deal.
Mrs May also says the government is preparing for no deal but is confident of leaving the EU with a “good deal”.
The UK is on course to leave the EU on 29 March and the government had previously ruled out another referendum.
She writes in the newspaper: “In the summer of 2016, millions came out to have their say.
“In many cases for the first time in decades, they trusted that their vote would count; that after years of feeling ignored by politics, their voices would be heard.
“To ask the question all over again would be a gross betrayal of our democracy – and a betrayal of that trust.”
It has also secured funding from donors including Julian Dunkerton, co-founder of fashion label Superdry – who has given the largest donation of £1m to the group. Thousands of supporters also took part in a march in central London in June.
The campaign is hoping to get enough MPs, including the Labour leadership, to back a call for a referendum on the deal Mrs May strikes with Brussels – which is due to be put to a vote in Parliament in October.
Earlier this week, it was revealed in a leaked memo that People’s Vote wants Labour MPs and activists to submit a motion at the party’s conference this month, committing Labour to backing a new referendum on the final deal. The party’s current policy position is to respect the result of the 2016 Brexit referendum.
The prime minister says the coming months are “critical in shaping the future of our country” but that she is “clear” about her mission in fulfilling “the democratic decision of the British people”.
She said that following the Chequers agreement in July, “real progress” had been made in Brexit negotiations.
While there is more negotiating to be done, Mrs May says “we want to leave with a good deal and we are confident we can reach one”.
The government has been preparing for a no-deal scenario, even though this would create “real challenges for both the UK and the EU” in some sectors, Mrs May says. But she adds: “We would get through it and go on to thrive.”
She says that she “will not be pushed into accepting compromises on the Chequers proposals that are not in our national interest”.