A Kurdish security officer escorts Alexanda Kotey and El Shafee Elsheikh at a security center in Syria. (Hussein Malla/AP)

Britain’s home secretary last month sent a letter to Attorney General Jeff Sessions, stating that his government would drop a demand that two alleged Islamic State militants be spared the death penalty if convicted in a U.S. court, in an apparent bid to resolve a standoff between the countries over which one should take custody of the men.

The June 22 letter by Sajid Javid to Sessions sparked an uproar in Britain when it was described on Sunday in the Telegraph, a British newspaper. In response, Prime Minister Theresa May, through a spokeswoman, said the government’s opposition to capital punishment remains unchanged.

That long-standing policy against the death penalty has been seen as one impediment to a prosecution in the United States of Alexanda Kotey and El Shafee Elsheikh, who allegedly belonged to a four-member Islamic State cell thought to have played a key role in torturing and killing American and British hostages. The men, whose British accents gave the cell its moniker the Beatles, were captured and detained in Syria.

U.S. prosecutors have requested that the British share evidence they’ve acquired, including a voice analysis that could aid in the identification of Kotey. But the British government had balked at sharing evidence without some assurance that it would not be used in a prosecution that might end in a death sentence.

Though some officials within May’s conservative government are not averse to capital punishment, the British public is staunchly against it. To reassure the public, Security Minister Ben Wallace on Monday told Parliament:“Our long-standing position on use of the death penalty has not changed. The U.K. has a long-standing policy of opposing the death penalty as a matter of principle, regardless of nationality.”

The two militants, whose British citizenship was revoked over their alleged affiliation with the cell, are being held in Syria, where they were captured in February by the Kurdish-dominated Syrian Democratic Forces, the main ally of the United States in Syria.

“I am of the view that there are strong reasons for not requiring a death penalty assurance in this specific case, so no such assurances will be sought,” Javid wrote in the letter, according to the Telegraph.

May’s office told reporters that there was no contradiction between the government’s opposition to the death penalty and Javid’s decision not to seek an assurance against execution.

“It’s an extraordinary statement about the British reluctance to prosecute these men, that they’re willing to withdraw requirements that they have imposed on U.S. cooperation for so long,” said Nicholas J. Lewin, a former counterterrorism prosecutor in Manhattan. “It strikes me as a finely honed effort to get the U.S. to take these guys and prosecute them.”

Some relatives of the victims, including the mother of James Foley, have spoken out against seeking the death penalty, saying they would prefer that the men serve life in prison.

The Telegraph also reported that according to other documents, British officials have assessed that Kotey and Elsheikh may be sent to the U.S. military detention facility at Guantanamo Bay and that such an outcome would not be formally opposed.

Wallace, the security minister, appeared to dispute that possibility, too. “The U.K. government’s long-standing position is that the detention facility at Guantanamo Bay should close. Where we share evidence with the [United States], it must be for the express purpose of progressing a criminal prosecution and we have made that clear to the United States.” he told parliament.

It is not clear what impact Javid’s letter to Sessions has had on Trump administration deliberations over how to handle the militants. Although career prosecutors think they can win at trial, Sessions personally favors sending the men to Guantanamo. And the position of the State and Defense departments has been that Britain, as the militants’ country of origin, should take them for prosecution.

The National Security Council declined to discuss the matter, issuing the following statement: “President Trump is committed to using all available tools to defeat terrorism and protect the United States homeland and its interests abroad. Decisions regarding the disposition of captured terrorists will be made on a case-by-case basis, taking into account legal requirements and the facts of each case.”

A Justice Department spokesman also declined to comment on the matter. “The president and his national security team will pursue the option that best protects the national security interests of the United States,” spokesman Wyn Hornbuckle said.

Christopher Costa, who until earlier this year was Trump’s senior director for counterterrorism and who now heads the International Spy Museum, said: “My bottom line is these individuals have to face justice, and right now the best form of justice would be the United States criminal justice system.”

Matt Zapotosky and Alice Crites contributed to this report.