As Swedish prosecutors consider reopening a probe into rape allegations against Julian Assange, the matter sets up a test of just how tangled the post-Brexit legal system is about to become.

British police arrested Assange, 47, last week, ending his seven-year stay in the Ecuadorian embassy in London. American authorities promptly asked the U.K. to extradite Assange to face charges related to the disclosure of secret government documents.

An extradition request from Sweden could delay that case if British authorities decide to prioritize a nine-year-old rape allegation that originally sent Assange into hiding.

Sweden issued an arrest warrant for Assange in 2010. He fought the extradition up to the U.K. Supreme Court, where he lost in 2012. While he was out on bail in that case, Assange sought asylum in Ecuador's embassy. As the years dragged on, Swedish prosecutors dropped the investigation because it had become impossible to pursue the probe in his absence.

Following Assange's arrest last week, a lawyer for one victim asked the Swedish prosecutor to reopen the investigation.

"I will of course continue to fight for my client to receive justice and reparation," the lawyer, Elisabeth Massi Fritz, said by e-mail. "Not many people think about the issue that there's a plaintiff, a woman, who has lived with trauma now for many years."

Lawyers for Assange didn't reply to e-mails seeking comment.

If Sweden does seek Assange, U.K. Home Secretary Sajid Javid would choose which request to address first. The secretary would have to weigh factors including the seriousness of the offenses and the date each warrant was issued, according to U.K. extradition law.

Last week, more than 70 U.K. lawmakers, mostly from the opposition Labour Party, signed a letter urging Javid to prioritize any Swedish request over the U.S.

"We must send a strong message of the priority the U.K. has in tackling sexual violence," read the letter, written by Labor MP Stella Creasy and signed by lawmakers including the Independent Group's Anna Soubry and Jo Swinson of the Liberal Democrats.

Diane Abbott, Labor's shadow home secretary, later replied to the letter to say the British government should extradite Assange to Sweden to face rape charges if the country makes a request.

Assange previously fought going to Sweden because he feared proceedings there would lead to a U.S. extradition request. Since the Americans have made a request in the U.K., he may no longer have a motivation to stay away from Sweden.

"The risk of being extradited from Sweden to the U.S. isn't larger than from the U.K." said Sven-Erik Alhem, a former chief public prosecutor in Sweden.

The U.K. may find the Swedish option compelling. A rape charge would be serious and would have a deadline in August 2020 when the statue of limitation will limit prosecution.

Extradition to Sweden could also be much speedier if Assange is processed under current European Union rules, according to Thomas Garner, an extradition lawyer at Gherson.

Still, no matter how fast the process goes, it could collide with the U.K.'s exit from the European Union. If the British Parliament approves the current withdrawal agreement, then the U.K. will maintain the status quo through the end of 2020. That's likely enough time to deal with any Swedish request even if it were drawn out in court.

But if there's a no-deal Brexit, all bets are off.

The political confusion would open up a litany of opportunities for Assange's lawyers to challenge the legal standing of Sweden's extradition request, according to Rebecca Niblock, a partner who specializes in extradition at Kingsley Napley.

"The whole Brexit thing is bad for lawyers in the long term, but in the short term we're quite excited about all the things we'll be able to argue," Niblock said.