JoJo Penn, who previously served as deputy chief of staff to Theresa May, met with Donald Trump numerous times during his first presidency, between 2016 and 2019.

Speaking to our podcast about electoral dysfunction, Ms Penn detailed how Sir Keir Starmer might deal with Trump, advising him to “expect the unexpected”.

She said: “He will raise a whole range of issues, from China and North Korea to his golf courses in Ireland to something he said on social media that day.

“He’s a pretty charismatic guy when you meet him in person. And I guess that shouldn’t be surprising given the kind of rallies he does in the United States.

“He can be very direct. You know, he’s a negotiator.

“And so he would say, tell me what you want or tell me what I can do for you. And having a very direct answer to that kind of direct question can often work in your favor.”

The former advisor recalled an instance when she met Trump at the G20 in Hamburg with Mrs May:

“It was actually a good meeting, which was well exceeded,” she said.

“There was an awful lot to discuss, but sometimes it can be difficult to keep President Trump on topic. So even though we were about 20 minutes over time at the end of the meeting, even though we raised a whole host of important topics, we realized we hadn’t addressed climate change.

“With Trump’s intention to withdraw the United States from the Paris Agreement.

“So we had to tell the Prime Minister that she needed to raise this topic with him. But fortunately, at the G20, the seats in the main conference room are arranged alphabetically.

“The British Prime Minister therefore always finds himself seated between the Turkish president and the American president.

“It wasn’t difficult for her to be able to talk to him on the sidelines of this conference.”

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