LONDON (AP) — U.S. Vice President Mike Pence is used to standing next to a pugnacious, unpredictable leader with no filter and much-studied hair.

On Thursday, he encountered another one as he met with embattled British Prime Minister Boris Johnson at No. 10 Downing Street, where the vice president tiptoed through the Brexit fury that has engulfed the region.

Wrapping up a week in Europe, Pence spent about a half-hour with Johnson, whose determination to lead Britain out of the European Union on Oct. 31 faces intense opposition from lawmakers, including members of his own Conservative Party, putting his leadership at risk.

The Brexit drama was mostly a whisper as the two exchanged pleasantries and Johnson cracked jokes that largely went over the heads of members of the traveling U.S. delegation.

It was all very pleasant as they chatted in front of reporters at the start of their meeting.

Johnson mentioned the "wonderful time" he'd had in France at a recent summit with President Donald Trump.

Pence thanked Johnson for the warm welcome at "a very busy time here in the United Kingdom."

"Always busy," Johnson returned.

Unreferenced was the tumult engulfing Johnson, whose very bad week got worse on Thursday when his younger brother, Jo, quit the government , saying he could no longer endure the conflict "between family loyalty and the national interest." A day earlier, lawmakers had rejected Johnson's bid to call an early election, making moves to stop him from taking Britain out of the EU at the end of next month even if there is no deal with Brussels to pave the way.

Pence largely stuck to script, delivering greetings from Trump and saying the president had asked him to assure Johnson that "the United States supports the United Kingdom's decision to leave the European Union."

The vice president said Trump also wanted him to convey that the U.S." is ready, willing and able to immediately negotiate a free trade agreement with the U.K." once it leaves the EU, which he predicted could multiply trade between the nation three or four times.

"Fantastic," Johnson responded, calling the U.S. economy "a wonderful, massive opportunity for U.K. folks."

The exchange glossed over the long and arduous process involved in negotiated a free trade deal, although Johnson did make note that "you guys are pretty tough negotiators."

Pro-Brexit British politicians have been pushing for a deal that would give them maximum freedom to strike new trade pacts with other countries, including the United States.

Johnson did press for the removal of U.S. trade barriers on British products including lamb and beef and haggis, a Scottish dish made with the lungs of sheep. He also mentioned trade barriers to shower trays — "would you believe it?" — a term for the flooring of showers.

While Johnson said he would do "everything to increase free trade," he made clear that Britain would resist any American attempt to weaken the state-funded National Health Service.

"And we're not too keen on that chlorinated chicken either," he quipped, adding: "We have a gigantic chlorinated chicken of our own here on the opposition bench."

The comment, which left others in the room visibly befuddled, was a reference to the U.S. practice of rinsing meat in chlorine at the end of the production process. Opponents believe the practice allows for lower animal hygiene standards and worry what will happen if it's allowed as part of a trade pact with the U.S.

Johnson has also used the term to insult opposition Labour Party leader Jeremy Corbyn.

An adviser to Pence said that even if some reporters were confused, Pence got the joke.

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