US President George W Bush was told more than a month before the September 11, 2001 terrorist strikes that supporters of Osama bin Laden planned an attack within the US with explosives and wanted to hijack airplanes,
according to a media report.

The warning came in a secret briefing that Bush received at his ranch in Crawford, Texas on August 6, 2001, an unnamed government official was quoted as saying by The New York Times on Friday.

The disclosure appears to contradict the White House's repeated assertions that the briefing the President received about the Al Qaeda threat was "historical" in nature and that the White House had little reason to suspect a Qaeda attack within the US borders, the daily said.

The Congressional report last year, citing efforts by Al Qaeda operatives beginning in 1997 to attack American soil,
said that Qaeda operatives appeared to have a support structure in the US and that intelligence officials had "uncorroborated information" that bin Laden "wanted to hijack airplanes" to gain the release of imprisoned extremists.

It also said that intelligence officials received information in May 2001, three months earlier, that indicated "a group of bin Laden supporters was planning attacks in the United States with explosives."

On Friday the White House offered evidence that  the Federal Bureau of Investigation received instructions more than two months before the September 11 attacks to increase its scrutiny of terrorist suspects inside the US, the daily said.
 
The disclosure appeared to signal an effort by the White House to distance itself from the FBI in the debate over whether the Bush administration did enough in the summer of 2001 to deter a possible terrorist attack in the United
States in the face of increased warnings, it said.

A classified memorandum sent around July 4, 2001, to National Security Advisor Condoleezza Rice from the counter terrorism group run by Richard A Clarke, described a series of steps it said the White House had taken
to put the nation on heightened terrorist alert.

Among the steps, the memorandum said, "all 56 FBI field offices were also tasked in late June to go to increased surveillance and contact with informants related to known or suspected terrorists in the United States."

Parts of the White House memorandum were provided to The New York Times by a White House official.