DONALD Trump praised Boris Johnson as a future Prime Minister.

The US President described the former Foreign Secretary as “a very talented guy”, adding: “I like him a lot.”

He said: “I have a lot of respect for Boris. He obviously likes me, and says very good things about me.

“I was very saddened to see he was leaving government and I hope he goes back in at some point.

“I think he is a great representative for your country.”

Asked if the ex-minister could be in No 10 one day, he replied: “Well I am not pitting one against the other.

“I am just saying I think he would be a great Prime Minister.

“I think he’s got what it takes.”

THERESA May must listen to her generals and hike defence spending to keep the Special Relationship intact, said Mr Trump.

His Secretary of Defense asked the UK Government to go significantly above Nato’s minimum target of 2 per cent of GDP in funding for its military as the US’s major ally.

The President told The Sun he agrees with Jim Mattis “100 per cent”.

He added: “Two per cent isn’t enough. The US pays 4.2 per cent of a much larger GDP.

“I’m very impressed that Jim sent that letter. I think that is an exact right letter.”

Mr Trump defended himself against allies’ charges of blackmail over his demand for rapid rises in all 29 Nato member states’ defence budgets.

Asked if he was a bully, he said: “I’ll tell you what, we’ve had 40 years of presidents saying the same thing in a nicer way and they got nothing, so call it what you want.

“They’re taking advantage of the United States. I’m not going to let it happen.”

Mr Trump caused panic by implying he could pull the US out of Nato if other countries did not hike their contributions.

He was asked at a Brussels press conference if he had threatened to withdraw and replied: “I told people I’d be very unhappy if they didn’t up their commitment. Yesterday I let them know I was extremely unhappy.”

He insisted nations had finally agreed to increase expenditure, adding: “Everyone in the room thanked me.”

But French President Emmanuel Macron denied Nato allies had agreed a spending rise.

The US wants its Nato allies to share more of the financial burden on defence.

In 2014 Nato nations committed to moves toward reaching the 2 per cent of GDP figure within 10 years.

Nato estimated just 15 members will meet the aim by 2024 based on current trends.