He is clever, cultivated, charming; witty, self-deprecating, wildly entertaining and oh so terribly British. Also dissembling, dishonest, dark, duplicitous, and a danger to his country and to Europe – a poker player whose bluff is about to be called.

As Boris Johnson settles into his new role, vowing, do or die, to take the UK out of the EU without a deal in 90 days unless the 27 nations ditch an accord that took two years to negotiate, European politicians and commentators are both fascinated and appalled.

“Like many people, I was easily charmed by his demeanour, his self-confidence, his intelligence,” said Han ten Broeke, a former Dutch MP specialising in EU affairs. “He’s a pleasure to listen to. I have a soft spot for Britain, and Boris was one reason why.”

Ten Broeke has since revised his opinion. “The charm, the intellect, the confidence – it all now looks a lot like over-confidence,” he said. “A promise of simple solutions to complex problems. And it could have disastrous consequences.”

The EU27 will give little, if any, ground on the withdrawal agreement, he said, and the costs of no deal are many times greater for the UK than for the EU. “So I can see only one reason Johnson might pursue it. A cynical, dark reason: new elections, to win a new mandate - putting party before country, at a truly existential moment.”

Another lifelong anglophile, André Gattolin, the vice-president of the French senate’s European affairs committee, said the new prime minister had carefully cultivated a “caricatural image – the hair, the gags, the flags, the zip-wire, the provocations”.

‘A carefully cultivated caricatural image’: Boris Johnson stuck on a zip-wire. Photograph: Barcroft Media

But behind the clownish persona was “a very smart strategist: after all, he’s in power, and he got there from inside the traditional structures. Yes, he has precious little room for manoeuvre and he’s soon going to run into reality; he’ll have to reach an accommodation, find something he can present as a victory.”

But his very presence in No 10 showed Johnson was not the bumbler the continental media like to portray him as, Gattolin said, adding: “He pretends he’s a bull in a china shop – but he knew how to get in, by the front door. He’s playing a game, and thus far you’d have to say he’s playing it pretty well.”

Some have direct – and chastening – experience of Johnson’s games. Martin Ehl’s 15-minute interview in November 2016 with the then foreign secretary won him brief international fame after Johnson was quoted dismissing as “bollocks” the notion that freedom of movement was a fundamental EU value.

Downing Street soon suggested Johnson had been misquoted – even though Ehl’s newspaper, Hospodářské noviny, had agreed to the British embassy checking the interview before publication. The Czech paper posted a recording of the interview on its website in which the offending expression is clearly audible, plus the words: “You can translate bollocks into Czech.”

Ehl said Johnson was “a politician and he does what he thinks is best for him”. Ehl said he had no problem with that, “but I do have a problem with someone trying to undermine our honesty and dignity … I saw in him a professional politician who knew he was talking to a journalist and that he had to say something that would resonate and make a good headline. But he wasn’t so careful.”

Pascal Boniface, the director of the French Institute for International and Strategic Affairs, agreed it was as much of a mistake for the French to mock Johnson as it was for them to laugh at Donald Trump. “We sit here jeering at them, and meanwhile they get on with putting their plans into action,” he said.

There were clearly similarities between the two leaders, Boniface said: both lead from the front, taking few hostages; both are opportunists, guided more by public opinion than any fixed ideology. But as far as Europe was concerned, he added, Johnson’s biggest problem was that the UK is not the US.

“The European reflex is still to show some deference to the US,” he said. “But the EU27 will not scrap the deal for Britain. The shock of reality will be brutal for Johnson – he may conceivably frighten Conservative MPs into backing him in parliament, but he won’t budge the EU.”

Italy’s former state secretary for European affairs Sandro Gozi now a Europe adviser to the French government, said Johnson was “a man who has changed his mind about quite a lot of things”, but had been “utterly consistent on Europe as prime minister: Britain must leave on 31 October. Well, we must respect that – but the question is, how will Britain leave? We await his proposal. The ball is in his court. A hard Brexit will be his choice.”

Reality is waiting in the wings, agreed Salvatore Margiotta, an MP with the Democratic party. Johnson is “a poker player who will now have to reveal his bluff”, he said. “We are facing a farce, a sort of Brexit fake. A no deal would have dramatic consequences, especially for the UK – and Johnson, who is prejudiced but not foolish, knows this.”

Ulrike Herrmann, economics commentator for the leftwing German daily Taz, concurred. It would be “intriguing to see when and how Boris Johnson effects his about-turn. Because he has a pragmatic relationship to power,” she said. “He became PM by posing as a hardliner. Long-term, though, he can only stay in this office if he says goodbye to a hard Brexit.”

Gabriel Felbermayr, the president of the Kiel Institute for the World Economy, suggested it would soon become clear whether Johnson really had a plan, but “with his provocative style, he is certainly not the person to build a bridge between his country, at odds with itself, and Brussels”.

Markus Becker, Spiegel’s Brussels correspondent, wondered whether Johnson was “simply going to let it come to no deal – in the hope that he will, as usual, be able to withdraw himself from the affair with a mix of chutzpah, charm and luck, and then pass the blame for the mess on to someone else”.

Bild’s lead opinion writer, Franz Josef Wagner, said Johnson had sprung from Britain’s “black and quirky” sense of humour: Mr Bean, Monty Python, anti-German jokes. “When things are bad in England, people laugh rather than complain about it,” he said. “I only hope they can continue to laugh under Boris Johnson.”

Some certainly doubt that. The Nobel literature laureate Mario Vargas Llosa, who lives in Spain, recently called Boris Johnson “a liar and a clown” and warned that he posed a threat to “Britain’s progress, civilisation and culture”.

But Carles Casajuana, who was Spain’s ambassador to the UK between 2008 and 2012 and met Johnson when he was mayor of London, recalled a “very intelligent, very nice” person. That was hidden, though, he said, behind an “air of frivolity: deep down, I think he’s much more calculating than he wants to show.”

Berta Herrero, a journalist specialising in the EU, said Spaniards tended to see Johnson as “kind of kamikaze”, and very loose on the facts. “He’s seen as reckless; as someone who has built a career on lying and convincing people of what’s on his mind: of his fantasies, not necessarily of the truth or the facts,” she said. “He is trying to copy Trump, but is more like his little brother.”

Additional reporting by Robert Tait in Prague, Sam Jones in Madrid, Kate Connolly in Berlin and Angela Giuffrida in Rome