French President Emmanuel Macron says “the door remains open” for Britain to change its mind about Brexit, after talks with Theresa May in Paris.

Mr Macron threw out the olive branch, even amid rising EU anger about the delays to the exit talks – which he said should be “launched as soon as possible”.

“Of course the door remains open, always open until the Brexit negotiations come to an end,” the President said, when asked if Britain could yet stay in the EU.

Mr Macron said it was not for him to say whether the decision should be questioned. “Once the negotiations have started we should be well aware that it'll be more difficult to move backwards.”

Alongside him, the British Prime Minister dodged a question about whether she would pursue a “softer” Brexit after her election setback, insisting there was a “unity of purpose” in the UK about leaving.

And she refused to respond to John Major’s warning of the danger of violence returning to Northern Ireland if she strikes a deal with the Democratic Unionist Party, to prop her up in Parliament.

Instead, on the withdrawal talks, Ms May claimed: “I confirmed to President Macron that the timetable for the Brexit negotiation remains on course and will begin next week.”

However, in Brussels, it was reported that the British delegation was unable to say on what date it wanted the talks to start when asked to do so by Michael Barnier, the European Commission's chief Brexit negotiator.

Almost certainly, they will not get underway next Monday as Ms May had promised repeatedly during the election campaign.

On whether the terms of Brexit would now change, the Prime Minister said only: "I think there is a unity of purpose among people in the United Kingdom.

"It's a unity of purpose, having voted to leave the EU, that their Government gets on with that and makes a success of it, and we are committed to developing a deep and special partnership with the EU.”

Intriguingly, Mr Macron's comments came just hours after Wolfgang Schäuble, the powerful German finance minister, sent out an identical message – saying the UK would find “open doors” in Brussels if it decided not to leave the EU.

In an interview with Bloomberg TV, Mr Schäuble said: “The British Government has said we will stay with the Brexit. We take the decision as a matter of respect. But if they wanted to change their decision, of course, they would find open doors.”

On Northern Ireland, Ms May insisted her Government was “absolutely steadfast” in its commitment to the Irish peace process after Sir John's dramatic intervention, warning that a DUP-Tory alliance would put fragile agreements at risk.

“We continue to work with all the parties in Northern Ireland and the Republic of Ireland in ensuring that we can continue to put in place those measures necessary to fulfil those agreements,” she said.

She went on: “What we are doing in relation to the productive talks that we are holding with the Democratic Unionist Party is ensuring that it is possible to, with their support, give the stability to the UK Government that I think is necessary at this time.

“We stand at a critical time with those Brexit negotiations starting only next week – I think that stability is important. We have worked as a party with the DUP before and those are productive talks. The intent is to ensure that we have the stability of Government in the national interest.”

Earlier, DUP leader Arlene Foster indicated that a deal to support the Conservatives' minority government is close to being finalised. It is expected to be concluded on Wednesday.

Observers noted that Mr Macron's welcome of the Prime Minister to the Élysées Palace was notably less warm than his greeting of Angela Merkel, the German Chancellor.