UK Foreign Minister Boris Johnson Grilled About His Anti-Hillary Clinton and Obama Comments

"Brexit" campaigner Boris Johnson would prefer instead to "get on with it."

LONDON— -- “Brexit” campaigner Boris Johnson squirmed awkwardly today during a joint news conference in London with U.S. Secretary of State John Kerry.

The newly appointed British foreign secretary blushed and bowed his ahead after reporters, most of them American, repeatedly asked him whether he plans to apologize to President Obama, Hillary Clinton and others for his past comments about them.

Johnson, known for his undiplomatic ways, once wrote that Obama harbored a “part-Kenyan’s ancestral dislike for the British empire,” and described Clinton in a newspaper column as "a sadistic nurse in a mental hospital.”

Johnson responded today, "I'm afraid that there is such a rich thesaurus now of things that I've said. It would really take me too long to engage in a full, global itinerary of apologies to all concerned."

The U.K.'s foreign secretary stressed, instead, the need to address important issues at stake.

Kerry struggled to conceal his smile as reporters asked him how he could trust "a man who lies.” Johnson, who successfully campaigned for the U.K. to leave the European Union, had supported the since-discredited claim that the country could save 350,000 British pounds a week (nearly $500,000) by a “Brexit.”

Kerry stuck to the high-ground today.

"Our ambassador to the E.U. in Brussels, who I just spent the evening with the other night, had the privilege of going to Oxford [University] with Boris Johnson," he said. "And he talked to me about some great experiences that they had together there, and he told me that this man is a very smart and capable man. That's the Boris Johnson I intend to work with."

Laughing, Johnson said, "Please, stop. That's fine, that's great. Thank you."

"It's called diplomacy, Boris,” Kerry said.

Reporters also pressed Johnson about his position on Syrian President Bashar al-Assad, whom he has previously praised for "saving Palmyra," the embattled city where ISIS militant have razed some of its ancient ruins.

Johnson interrupted a U.S. journalist, who was the third to ask him about his previous comments, saying, "Look, I appreciate your First Amendment, the freedom of the press, but let me repeat what I said," before saying it was "more important" to "get on with it."

Kerry, after describing his first meeting with the newly appointed minister, said, "I know Boris is fully prepared to jump into our agenda and has the readiness to see it through, with same sense of purpose [as his predecessors]."