Boris Johnson was left red-faced after a grilling by US journalists during his first London press conference as foreign secretary.
He hung his head as he was asked to explain his previous comments about world leaders.
And his US counterpart John Kerry winced as Johnson was accused of telling "outright lies" during his career as a journalist.
Johnson has previously remarked that US President Barack Obama harboured a part-Kenyan's "ancestral dislike for the British Empire".
And he was quoted saying presidential hopeful Hillary Clinton was someone with "dyed blonde hair, pouty lips and a steely blue stare like a sadistic nurse in a mental hospital".
However, he remain relatively bullish, turning down an invitation to apologise to all those he may have offended and insisting that his comments had been taken out of context.
We can all spend an awfully long time going over lots of stuff I have written over the last 30 years ...all of which, in my view, has been taken out of context, but never mind.
He added there was a "rich thesaurus" of comments he had made in his journalistic career and joked that it would take "too long" to issue an apology for all the things he had written which had been "misconstrued".
In another slip up, he twice referred to the crisis in Egypt - but was believed to have been talking about Turkey.
Meanwhile, Kerry told journalists Johnson was "very smart and capable man".
Johnson blustered his thanks saying: "It's called diplomacy!"
The US secretary of state did not make the best of starts to his trip to Number 10 - when he whacked his head on the door on the way in.
But he seemed to recover quickly and was later pictured chatting with May inside Downing Street.
After the talks, Kerry said the prime minister was committed to a "calm, thoughtful, reasonable" way to deal with Brexit.
"The prime minister and I had an excellent discussion and I'm very grateful to her for her restatement of the commitment to the very strong transatlantic partnership," he said.