KUALA LUMPUR, Malaysia — A Malaysian recruited by al-Qaida to pilot a plane in a second wave of Sept. 11-style attacks on the United States pulled out after observing the carnage of the first assaults, Southeast Asian officials said today.

President Bush on Thursday disclosed an alleged plot to hijack an airliner and fly it into a skyscraper in Los Angeles. He said cooperation between Washington and several Asian countries helped expose it.

The plan never appeared close to the stage where it could be put into execution. Scores of arrests in the aftermath of the Sept. 11, 2001, attacks severely curtailed al-Qaida and its Southeast Asian affiliate, Jemaah Islamiyah.

Adding details to Bush's outline, security officials and terrorism experts in Southeast Asia on Friday said Malaysian engineer Zaini Zakaria was among three men al-Qaida was preparing to take part in an attack on the U.S. West Coast.

Zaini, 38, traveled to al-Qaida camps in Afghanistan in 1999, where he met senior figures in the terrorist group, including Indonesian Riduan Isamuddin, or Hambali, a Malaysian security official told The Associated Press on condition of anonymity.

When he returned to Malaysia the same year, Zaini enrolled in a flight school and obtained a license to fly a small plane. He then began making inquiries in Australia about getting a license to fly a jet, the official said.

But Zaini was never told what his mission for al-Qaida would be. When he saw media coverage of the Sept. 11 attacks, he severed his ties with the militants.

Zaini, who has been detained without trial in Malaysia since he surrendered in December 2002, told Malaysian interrogators that he "didn't want that kind of Jihad," an official familiar with the interrogation told the AP.

A senior police officer involved in the interrogation, who spoke on condition of anonymity, said Zaini told his Malaysian interrogators "he was not prepared to die as a martyr, so he backed out."

The possible "second wave" attack was mentioned briefly in the June 2004 U.S. National Commission report on the Sept. 11 attacks on the World Trade Center and Pentagon.

It quoted Khalid Shaikh Mohammed, the reputed mastermind of the Sept. 11 attacks who was captured in 2003, as saying "three potential pilots were recruited for the alleged second wave." It identified them as Zacarias Moussaoui, Abderraouf Jdey, and Zaini.

However, Mohammed told his U.S. interrogators that "he was too busy with the 9/11 plot to plan the second wave of attacks," the report said.

Bush's disclosure has strained relations between the White House and Los Angeles Mayor Antonio Villaraigosa, who said he got word of the new details like everyone else — by watching Bush's speech on TV Thursday.

The mayor accused the Bush administration of taking too long to tell him of the new information.

Bush said terrorists intended to use shoe bombs to hijack an airliner and crash it into downtown's 73-story US Bank Tower.

As it turns out, the White House did notify City Hall, if indirectly. A spokesman for Matt Bettenhausen, California's homeland security chief, said he personally contacted a deputy mayor Wednesday afternoon with advance notice of the president's comments.