EMMANUEL Macron has delivered a firm Non to Boris Johnson’s hopes of scrapping the backstop by insisting that the fall-back guarantee to keep the Irish border open is “indispensable”.

The French President agreed to Angela Merkel’s 30-day challenge but gave little hope that, within such a tight timescale, it would be possible to produce a new withdrawal agreement "very different from the existing one".

Boris Johnson, however, continued to express a can-do spirit, saying he had been “powerfully encouraged” by his conversation the night before with the German Chancellor.

"Let’s get Brexit done,” declared the Prime Minister. “Let’s get it done sensibly and pragmatically and in the interests of both sides and let’s not wait until October 31. Let's get on now in deepening and intensifying the friendship and partnership between us.”

Amid a good deal of bonhomie at the Elysee Palace, Mr Johnson was adamant that Britain wanted a Brexit deal and believed that with “energy, creativity and application we can find a way forward”.

But Mr Macron, who the day before warned a no-deal outcome would lead to the “historic vassalisation of Britain” under America’s control, firmly rebutted any notion that the EU was about to cave in to the UK’s demands.

At a brief joint news conference in Paris, the President noted that while he had been portrayed as the EU’s "hard boy," he was simply being clear about where he stood on protecting and strengthening the European project.

He explained: “The key elements of this agreement, including the Irish backstop, are not just technical constraints or legal quibbling, but indeed genuine, indispensable guarantees to preserve stability in Ireland [and] to preserve the integrity of the single market which is the foundation of the European project.”

Mr Macron said that “we need visibility in 30 days” but equally pointed out how it would not be possible to find a new withdrawal agreement "very different from the existing one" within this timescale.

However, Mrs Merkel clarified her remarks about her “blistering timetable,” saying: “It is not about 30 days. The 30 days were meant as an example to highlight the fact that we need to achieve it in a short time.”

Some of Mr Macron’s remarks encouraged the more optimistic British diplomats, particularly when the President noted: "We should all together be able to find something smart within 30 days if there is goodwill on both sides," adding that the Withdrawal Agreement “can be amended” if the changes complied with his two goals of maintaining the integrity of the single market and the stability of Ireland.

The PM told his host that securing such changes, which met his two tests, was indeed do-able but noted that while he wanted a new agreement, the UK "must come out of the EU on October 31; deal or no-deal".

Mr Johnson again made clear the UK, “under no circumstances,” would introduce a hard border with the Irish Republic.

"We think there are ways of protecting the integrity of the single market and allowing the UK to exit from the EU, all and entire and perfect as it were,” Mr Johnson argued, referring to alternative arrangements like trusted trader schemes and electronic pre-clearing of goods.

Britain’s pugnacious premier ended the press conference, declaring: “Where there’s a will, there’s a way.”

The two leaders joked with each other in front of the TV cameras before they headed in for lunch to talk Brexit.

For two hours they chatted, a conversation that took in a walk through the Elysee’s palatial gardens. Mr Johnson later emerged smiling and waving as he got into his Range Rover, adorned with Union flags, to return home.

The subject of Brexit will be on the agenda in just 24 hours’ time when Mr Macron and his guest travel to Biarritz for the G7 summit. But other matters such as global trade, climate change, Russia’s readmission as well as the foreign policy issues of Iran, Yemen and Hong Kong are likely to dominate the talks.

However, the bonhomie is likely to continue as Mr Johnson has his first meeting with Donald Trump.

The US President has sung the praises of the PM, whom he has described as “Britain Trump”. It has been suggested that to underscore his admiration for Mr Johnson he will see him first before meeting his host, Mr Macron.

The expectation is both men will wax lyrical about the prospect of a post-Brexit trade deal; their glad-handing pictures are set to dominate the weekend news coverage; in Britain, at least.