Boris Johnson has had his first substantive talk since taking office with President Donald Trump, who has described the UK’s Prime Minister as the British Trump (“Britain Trump”).

After their telephone conversation on Friday, both sides talked up the prospects for a US-UK free trade agreement of the kind Britain will also want to sign with the world’s two other major economic powers — China and India.

So far, India has not got overexcited at the change of leadership in London since Narendra Modi’s government knows nothing can be signed until Britain has actually left the EU.

But Trump told reporters at the White House: “We’re working already on a trade agreement. And I think it’ll be a very substantial trade agreement. You know we can do with the UK, we can do three to four times, we were actually impeded by their relationship with the European Union. We were very much impeded on trade.”

Trump said the UK had “needed” Boris for a long time, adding: “He has what it takes.”

“I think we can have a great relationship and Boris is going to be a great Prime Minister,” he said. “I predict he will be a great Prime Minister.”

There is no doubt Boris has brought a new sense of optimism and great entertainment to British politics. But although he has committed him to taking Britain out of the EU by October 31 — “no ifs or buts” — there are serious doubts about whether this can be done given he does not have the numbers in the Commons.

Boris has “absolutely” ruled out calling a general election before October 31 but he has not said what he would do if a no deal Brexit is blocked by the Commons.

He has told the EU that the withdrawal agreement negotiated over three years by Theresa May has to be reopened and the Irish “backstop” abolished. To which the EU have said neither is going to happen.

The Trump-Boris talks are a chance to try and repair the serious damage to the transatlantic relationship caused by the leak of confidential diplomatic telegrams sent to London by Kim Darroch, who described the US administration as “inept” and “dysfunctional”.

The US President and the British Prime Minister “agreed that Brexit offers an unparalleled opportunity to strengthen the economic partnership between the UK and United States,” said a Downing Street spokesman.

“The leaders both expressed their commitment to delivering an ambitious free trade agreement and to starting negotiations as soon as possible after the UK leaves the EU.”

The spokesman added: “The Prime Minister and the President also discussed the current tensions with Iran and the need to work together and with partners to address their destabilising behaviour in the Gulf.”

Although the tanker seized by the Iranians, the Stena Impero, is British-flagged, there are no UK nationals on board. Of the 23 crew, 18 are Indians, which explains why the story has gone off the boil in the British media, with no great pressure on Boris to free the hostages.

There is recognition that Britain will probably have to free the Iranian tanker it seized off Gibraltar, Grace I, as part of any settlement.

Downing Street said that Trump used the call to “congratulate” the PM on his new role. “They discussed the important relationship between our countries and the President’s successful state visit to the UK last month.

“They ended by looking forward to seeing each other at the G7 Summit in Biarritz next month.”

Meanwhile, Boris has completed second and third tier appointments in government. There is no place for the competent Indian origin Shailesh Vara who resigned as Northern Ireland minister in May’s government and now risks being forgotten.

However, at the foreign office he has retained the services of the peer, Tariq Ahmad, an Ahmadiyya Muslim with links to both Pakistan and India. He deals, among other issues, with the Commonwealth and the persecution of Christians all over the world.

Nusrat Ghani, who is of Pakistani origin and has in the past attacked India’s human rights record in Kashmir, has kept her job as a transport minister and has also been made an assistant government whip.

But there is no room for Mark Field, the foreign office minister who had enjoyed dealing with India. In any case, he was “suspended” after a video of him grabbing a woman climate change protestor by the neck at a formal dinner went viral.

Picking out the well-heeled cabinet ministers in Boris’s cabinet, the Daily Mail focused on Rishi Sunak, 39, the chief secretary to the treasury. He is said to be “so wealthy he’s dubbed the Maharaja of the Dales”.

“By far the most glamorous invitation in the North Yorkshire social calendar is to the summer garden party in the landscaped grounds of the magnificent Georgian manor house in a small village,” it said.

“Uniformed staff serve champagne and canapés as guests mingle alongside the ornamental lake with its boathouse, private wooded island and paddocks set in 12 acres.

“The host is Rishi Sunak, the MP for Richmond in the county … He bought the house for £1.5 million in 2015.”

His wife, Akshata, “herself runs fashion label Akshata Designs and is also a director of a venture capital firm founded by her father (Infosys founder N R Narayan Murthy) in 2010”.

The Mail story carries a quote from David Hugill, a local Tory councillor who appears to be have been impressed by Indian

hospitality: “We see plenty of him and his garden parties are great occasions. He brought Boris Johnson to one of our fundraising events just a few weeks ago. It was sold out. Rishi’s wife has really thrown herself into the job, too. They are an asset to the area.

“i think he can go much further than his current cabinet job, maybe all the way to the top.”

The Mail predicted that because of the politics of envy, “Labour’s attack dogs will target the fact Mr Sunak, who boarded at the £40,000-a-year Winchester College and is believed — thanks to his marriage — to be the richest MP, has been handed the sensitive task of balancing the books at the Treasury”.