U.S. officials believe that a letter partially drafted by a U.S. postal worker now in custody may have had a role in the death of an Afghan resistance leader, the Washington Post reported on Monday.

U.S. authorities believe that Ahmed Abdel Sattar, 42, helped write a letter of introduction for two men who posed as journalists to kill Gen. Ahmed Shah Massoud in northern Afghanistan last fall, the Post said.

Sattar, an Egyptian-born U.S. citizen, has not been charged in Massoud's murder on September 9, 2001.

But a conversation in the summer of 2001 about the letter surfaced during a wiretap involving Sattar, who is charged with serving as a communications centre for an Egyptian terrorist group allegedly directed by Sheikh Omar Abdel Rahman from his U.S prison cell, the Post reported.

Abdel Rahman was convicted in 1995 of plotting to blow up New York landmarks, including the World Trade Centre.

U.S. authorities believe that Massoud was killed as a preemptive strike in advance of the attacks on the World Trade Centre and Pentagon two days later that killed more than 3,000 people, the newspaper said.

Another Egyptian man who allegedly helped draft the letter, Yassir Sirri, has been charged by Britain with conspiring to kill Massoud.

Sirri has denied any involvement in Massoud's death, the Post reported. "It's clear that this was a letter for these two guys (Massoud's killers)," an official, who asked not to be named, told the Post. "But how much Sattar knew about the mission isn't clear."

Sattar, a 13-year veteran of the U.S. Post office, earned $40,000 per year working at the main post office in Staten Island, New York. He has pleaded not guilty to the charges.

According to Sattar's indictment, an Islamic group leader asked him to help expand the group's presence in the United States three years ago.

The group has taken responsibility for the 1997 massacre at Luxor, Egypt in which 58 tourists and four Egyptian security guards were hacked and shot to death.

Since his arrest on April 9, Sattar has not been allowed a visit from his family or a telephone call, the Post said.