LONDON — Nigel Farage’s Brexit Party showed up for work on Tuesday and their first act was to turn their backs on the institution they wished they were not a part of.

Farage, the leader of the months-old party, tweeted that the lawmakers in the Brexit Party arrived at work in Strasbourg, France, and would be “cheerfully defiant” and “they’ll know we’re here!”

That was indeed the case.

The European Parliament reopened on Tuesday for its first official sitting following elections held in May. There was an opera singer and a saxophone quartet that played Beethoven’s “Ode to Joy,” the E.U.’s anthem.

Initially, the 29 members of the Brexit Party refused to stand. When they finally did, they turned their backs. 

The Brexit Party is a single issue party — it wants Britain out of the European Union. The members sitting in the chamber on Tuesday wish they weren’t there at all and that Britain had already left the bloc, as it was scheduled to do on March 29. It’s unclear how long they will stay in their posts, but it could be as little as four months if Britain exits the E.U. on Oct. 31, the new deadline.

It’s also unclear how disruptive they may be. Farage, who has been a member of Parliament since 1999, is known for his acerbic speeches and being a thorn during debates, but he also doesn’t always show up for work. 

The Brexit Party was the clear winner in the European elections in Britain, which sent 73 lawmakers to the European Parliament. But the vote was fractured, with those unambiguously opposing Brexit doing well also.

The collective support for those parties unashamedly pro-European was slightly higher than those advocating a hard Brexit.

At the session on Tuesday, the pro-E.U. Liberal Democrats tried to make their presence known as well, wearing bright yellow T-shirts that said “Stop Brexit.”

The ascent of the Brexit Party has terrified the ruling Conservatives, who worry that the party will continue to eat into their vote share unless they deliver Brexit — the Conservatives won only 9 percent of the vote in the European elections.

Many analysts say that the rise of the Brexit Party, which is comfortable with Britain leaving the E.U. without a deal and adopting a trade relationship based on World Trade Organization (WTO) rules, has boosted the chances of Boris Johnson becoming the next British prime minister.

Unlike his opponent Jeremy Hunt, Johnson voted in favor of leaving the E.U., and he also appears to be less concerned than Hunt about possible risks of leaving the union without a deal.

The majority of lawmakers in Parliament oppose leaving the E.U. without a firm plan. They have raised concerns about possible medical shortages and traffic jams for trucks heading to the continent that would suddenly have to deal with customs controls.

Most Conservative Party members, who will select the next prime minister, are in favor of a “no-deal” Brexit, however.

“A lot of the negativity about a WTO Brexit has been wildly overdone,” Johnson said on Tuesday at a campaign event. “People say there won’t be any clean drinking water and planes won’t fly and there won’t be milk solids and glucose and whey to make Mars bars.”

Those disruptions won’t happen, he said, and, in typical Johnsonian fashion, made light of the situation. “There will be whey for the Mars bars,” he proclaimed, “because where there is a will, there is a way.”