KABUL, Afghanistan — The suicide bomber who killed Afghanistan’s former president, Burhanuddin Rabbani, gained access to him by presenting officials beforehand with an audio recording of a purported Taliban peace offer, President Hamid Karzai said Thursday.

At a news conference, Karzai said the CD was a trick to allow the assassin to get an appointment with Rabbani, who led the country’s High Peace Council. Karzai’s remarks offered new details about Rabbani’s death, which dealt a devastating blow to efforts of negotiating a peace settlement with the Taliban to end the decade-long war.

The assassin, who hid a bomb in his turban, killed the 70-year-old former Afghan leader Tuesday at his home in Kabul.

Karzai said that before he left for New York last weekend, one of his advisers, Mohammad Masoom Stanekzai, told him that the Taliban had a message for the Afghan peace council. Stanekzai is a top peace council official who was wounded in the attack that killed Rabbani.

“Stanekzai brought me a message that someone had come from the Taliban movement and brought with them an audio CD in which there was a message from a Taliban representative,” Karzai said.

The president said he listened to the audio before leaving to attend the U.N. General Assembly. The voice on the recording spoke respectfully about Rabbani, he said. “There were a couple of questions and suggestions mentioned regarding peace.”

Karzai said he then talked with Rabbani, who rushed back home from a trip to Iran to listen to the recording.

“It was not a peace message. It was a trick,” said Karzai, speaking at a podium set up in a courtyard of the presidential palace. “The messenger was the killer.”

Shafiqullah Tahiri, a spokesman for the Afghan intelligence service, said officials believe Rabbani’s killing had been planned for four months and that the Afghan Taliban’s governing council known as the Quetta Shura, named after the city in Pakistan, was behind the assassination.

No one has claimed responsibility for the attack. When contacted by The Associated Press, Taliban spokesmen declined to discuss the killing and spokesman Zabiullah Mujahid said they were still investigating the killing.

Rahmatullah Wahidyar, a member of the peace council who had brought the bomber to Rabbani’s house, told reporters that when the attacker entered the room, Rabbani stood up and went to hug him.

“There was a bang,” Wahidyar told reporters at a news conference held by the intelligence service. “I have small fractures on my face and right side.”

Shortly after Karzai’s remarks, U.S. Ambassador Ryan Crocker pledged support from the United States and international community for Afghan peace efforts, and called Rabbani’s killing a “brutal murder.”

“It demonstrates the utter disregard that the terrorists have for Afghans and the future of this country,” Crocker said.

He also said that Rabbani’s death “raises very serious questions” as to whether the Taliban and those who support them have any real interest in reconciling with the Afghan government. “This is a sad time, but it is not a time for despair,” Crocker said.

Also Thursday, NATO said Afghan and coalition forces killed the top Taliban leader in Tangi Valley who was being tracked in an operation in which a CH-47 Chinook helicopter was shot down Aug. 6, killing 30 American troops, mostly elite Navy SEALs.

According to the alliance, the Taliban leader, Qari Tahir, and one of his associates were killed Tuesday in a dry riverbed in Sayd Abad district of Wardak province. The coalition said Tahir coordinated ambushes against Afghan forces and orchestrated kidnappings and hijackings of convoy vehicles.

NATO also has reported that a service member died Wednesday as a result of a non-battle related injury in southern Afghanistan. Two other service members were killed Wednesday in an insurgent attack in the south, according to the alliance. No other details were disclosed.

The latest deaths bring to 434 the number of international troops killed so far this year in Afghanistan.