ISLAMABAD, Pakistan — The lawyer for a man convicted of killing Wall Street Journal reporter Daniel Pearl said yesterday that he will file an appeal using an Al Qaeda lieutenant’s recent confession that he beheaded the reporter.

Khalid Sheikh Mohammed, who has claimed that he planned the September 11, 2001, attacks, said at an American military hearing at Guantanamo Bay, Cuba, that he personally beheaded Pearl for being an Israeli intelligence agent.

“I decapitated with my blessed right hand the head of the American Jew, Daniel Pearl, in the city of Karachi, Pakistan,” Mr. Mohammed told a military panel, according to a Pentagon transcript released yesterday. “For those who would like to confirm, there are pictures of me on the Internet holding his head.”

In 2002, an anti-terrorism court in Karachi sentenced Ahmed Omar Saeed Sheikh, a British-born militant, to death and gave three other men life in prison for involvement in Pearl’s killing.

Rai Bashir, who is a lawyer for Sheikh and the other three men, said yesterday that he will study the Pentagon documents on Mr. Mohammed’s claim and file his confession as evidence to prove Mr. Sheikh’s innocence.

“He has not abducted Daniel Pearl, and he, along with his co-accused, is innocent … But now we are happy that this version has been verified by the Pentagon after the arrest of Khalid Sheikh Mohammed,” Mr. Bashir told AP Television News in a separate interview on Saturday.

Pearl was abducted in January 2002 in Karachi while he was researching a story on Islamic militancy. Months after his abduction, the journalist’s body, his throat slit, was found in a shallow ditch in a compound on the outskirts of the city.

Mr. Sheikh and the three others — Salman Saqib, Fahad Naseem, and Sheikh Adil — are in jail and have appealed their convictions.

“What we were saying for so many years in our trial, in the appeal, [is] that Ahmed Omar Saeed Sheikh is innocent, and he has not committed that murder,” Mr. Bashir said in the interview from the eastern city of Lahore.