By Leigh Thomas

PARIS (Reuters) - Modestly shaking his head to deny he was any good at speaking French, Britain's new foreign minister Boris Johnson sought to charm a media audience in Paris during a joint appearance with his French counterpart, who recently called him a liar.

At a news conference after private talks, Johnson and Jean-Marc Ayrault exchanged assurances of friendship but left without taking questions from a roomful of journalists eager to probe the awkwardness behind the niceties.

Johnson was the leading figure in the campaign for Britain to leave the European Union ahead of a June 23 referendum that resulted in a vote for Brexit and plunged the 28-member bloc into crisis and soul-searching.

After Johnson's shock appointment as foreign secretary by new Prime Minister Theresa May, Ayrault said on French radio that Johnson had lied to the British people during the campaign and now had his back to the wall.

Johnson was later booed at a Bastille Day reception at the French ambassador's residence in London.

Neither man made any reference to these undiplomatic events during Thursday's appearance together in the gilded surroundings of the Quai d'Orsay, France's grand foreign ministry building on the banks of the Seine.

Ayrault kicked off proceedings with pleasantries, saying he was delighted to greet Johnson in the ornate Salon de l'Horloge, or Clock Room, prompting Johnson to look up toward the ceiling and from side to side, apparently searching for a clock.

"He is well known in France, and not only for his excellent biography of Winston Churchill but also as mayor of London. He knows France well in fact, and speaks French very well," said Ayrault. Johnson demurely looked down and shook his head.


"I have even been told, dear Boris, that your family on your mother's side has origins in the region of Nantes, my city," continued Ayrault, seeking some common ground.

Recognized around the world thanks to his disheveled platinum hair, Johnson is also known for gags and insults often delivered in colorful, erudite language peppered with Latin.

When it was his turn to speak, Johnson did so in accented but correct French, saying he was delighted to be in France for his first bilateral visit to a European country as foreign secretary.

Reading from prepared remarks, he stuck to the script and avoided any jokes as he sought to project a more serious image than in the past. He later said he had a "warm" two-hour working lunch with Ayrault before their media appearance.

Previously, Johnson had sought to minimize Ayrault's disobliging comment, saying he had received "a charming letter" from the French minister congratulating him on his new job.

At a news conference with his U.S. counterpart John Kerry in London last week, Johnson was assailed by questions from U.S. reporters about past jibes at the likes of President Barack Obama and presidential candidate Hillary Clinton.

Although the tables were turned on Thursday and Johnson found himself in the rare position of being the one who had been insulted rather than the author of the insult, neither he nor Ayrault were taking any chances.

After both men made their remarks and shook hands for the cameras, they walked out, leaving awkward questions unanswered.

(Additional reporting by Andrew Callus; writing by Estelle Shirbon in London; editing by Giles Elgood)