A bomb warning dated two days before Pan Am Flight 103 was destroyed over Scotland was an unimportant document and was mailed after the disaster, the transport secretary said in an interview published Friday.

"It went out after Christmas. I cannot tell you the exact date but some days after Christmas," the secretary, Paul Channon, was quoted by The Times of London as saying. "It was not a great new warning which we had to send out by telex. It was a bit of supplementary information containing some color photographs," the newspaper quoted him as saying.Disclosure of the Dec. 19 letter, warning of a radio-cassette bomb such as the one that has been identified as killing 270 people in the Pan Am disaster, brought new demands from opposition lawmakers for a full public inquiry.

Published reports that investigators have identified and even arrested a suspect in the bombing were denied by authorities in Britain and West Germany.

As criticism mounted of the government's handling of bomb warnings, a spokesman for the governing Conservative Party pointed a finger at Pan Am.

"The truth of the matter is that the West German authorities told Pan Am about a bomb in early November. The American government told Pan Am about it on Nov. 18," Conservative lawmaker David Wilshire said Friday. "So what has it got to do with the British government? Is Pan Am deaf or not?"

Pamela Hanlon, a Pan Am spokeswoman in New York, confirmed Friday that the airline received a warning from the West German government on Nov. 10 and another warning from the U.S. Federal Aviation Administration on Nov. 18.

The Times of London, quoting unidentified government sources, reported Friday that authorities know who bombed Flight 103. But the report was denied by British officials and an official in West Germany, where the flight originated.

"I can confirm to you that there is insufficient evidence to establish the identity of the person or group responsible for this," said Inspector Tom McCulloch, a spokesman for the crash investigation in Lockerbie, Scotland. He said there were no plans for an announcement as reported by the newspaper.