Vice President Dick Cheney opposed a promotion for a deputy involved in a heated dispute with the White House over the legality of a controversial domestic surveillance program, former Deputy Attorney General James Comey told senators.

Responding to written questions from members of the Senate Judiciary Committee, Comey implicated Cheney's office in thwarting the appointment of Patrick Philbin as deputy solicitor general in the wake of the dispute over the National Security Agency surveillance program.

"I understood that someone at the White House communicated to Attorney General [Alberto] Gonzales that the vice president would oppose the appointment if the attorney general pursued the matter," Comey wrote. "The attorney general chose not to pursue it."

During direct testimony in May, Comey had told senators he believed Philbin's promotion had been thwarted because of his involvement in a dramatic March 10, 2004, confrontation in the hospital room of then-Attorney General John Ashcroft over the classified program. (Read how Ashcroft was pressed to confirm the NSA program)

His comments about Cheney's alleged involvement in that decision came in answers to written follow-up questions posed by senators, which CNN obtained Wednesday.

Cheney's office had no immediate comment on Comey's characterizations. But Sen. Charles Schumer, D-New York, a member of the Judiciary Committee, said Comey "has confirmed what we suspected for a while -- that White House hands guided Justice Department business."

Schumer: Cheney strong-armed Justice

"The vice president's fingerprints are all over the effort to strong-arm Justice on the NSA program, and the obvious next question is, exactly what role did the president play?" Schumer said in a statement.

Comey testified that after the Justice Department refused to reauthorize the legality of the classified program in March 2004, Gonzales, then the White House counsel, and Andy Card, then White House chief of staff, went to Ashcroft's hospital room to try to get him to overrule the decision.

At the time, Ashcroft was seriously ill and had turned over leadership of the Justice Department to Comey, his chief deputy. Ashcroft refused to overrule Comey and recertify the program, Comey testified.

Philbin, then a deputy to Comey handling national security matters, was at the hospital that night and had recommended against reauthorizing the program, Comey said.

In his written answers, Comey also identified eight Justice Department officials he said were prepared to resign over reauthorization of the program, including himself, Philbin and FBI Director Robert Mueller.

But after Comey and Mueller met with President Bush two days after the confrontation in the hospital, the program was altered to satisfy the Justice Department's concerns and was then reauthorized, Comey testified.

The NSA program allowed interception of communications between people inside the United States and suspected terrorists overseas without first obtaining a warrant. Bush publicly acknowledged its existence in 2006, setting off a firestorm in Congress, where critics charged it infringed on civil liberties.

Ashcroft resigned in November 2004 and was replaced by Gonzales. Comey announced his resignation in March 2005.