WASHINGTON (AP) — President Joe Biden has refused to approve some of the conditions that lawyers for the defendants in the Sept. 11, 2001, attacks had sought in a possible plea bargain, ruling out a presidential guarantee that the five men would be spared solitary confinement and provided care for the trauma of their torture in CIA custody, a White House National Security Council official said Wednesday.

Biden’s refusal on the plea-bargain guarantees leaves it to military prosecutors and defense lawyers to try to hash out an agreement on a plea bargain. The terms under discussion would have the five Guantanamo detainees plead guilty and serve life sentences in exchange for being spared the death penalty.

Lawyers for the two sides have been exploring a negotiated resolution to the case for about 1 1/2 years. They had been waiting for about a year of that time to see if Biden would express opposition or support for some of the conditions that defense lawyers had been seeking.

Biden agreed with Defense Secretary Lloyd Austin’s recommendation not to accept the proposed terms as a basis for plea negotiations, according to the National Security Council official, who was not authorized to comment publicly and spoke on the condition of anonymity.

Biden was unsettled about accepting terms for the plea from those responsible for the deadliest assault on the United States since Pearl Harbor, the official said.

The White House had been reluctant to weigh in on the matter. Biden believed that the decision was the responsibility of the senior military official overseeing the U.S. military proceedings at Guantanamo Bay, Cuba, according to another person familiar with the matter who also was not authorized to comment and spoke on condition of anonymity.

The five defendants include Khalid Sheikh Mohammed, accused as the architect of the attacks, which were waged by commandeered commercial jetliners. The al-Qaida plot killed nearly 3,000 people outright in New York, the Washington, D.C.-area and Pennsylvania. The attack also changed the course of U.S. foreign policy and sparked deadly U.S. military invasions of Afghanistan, which had hosted al-Qaida, and Iraq, which had no role in the plot.

Pretrial hearings for the five have been under way at the U.S. military commission at Guantanamo Bay for more than a decade, with no trial date set. Legal questions, including the legal ramifications of the torture the men underwent after capture in the years immediately after the attack, have complicated the case. So have the logistical challenges of holding the proceedings outside the United States.

Announcement of Biden’s decision not to accede to some of the conditions sought by defense lawyers comes after U.S. military officials formally notified a widened circle of family members of 9/11 victims of the terms of the plea negotiations that were underway. Several of the survivors then spoke out publicly against a deal that would spare the five accused a trial and the risk of a death penalty.

Brett Eagleson, whose father was killed in the 2001 attacks, welcomed the administration’s decision. “We look forward to the day that we can praise our government for finally giving us justice and holding all parties involved in the attacks accountable,” he said in a statement.