Intelligence services have warned Tony Blair that the threat to Britain from terrorist attacks remains as high today as in the immediate aftermath of the 11 September attacks.
They have told ministers there is no evidence al-Qa'ida's suspected international network of terrorist sleepers has been broken up by the military action in Afghanistan.
The intelligence briefing – described by one senior minister as "chilling" – was aimed at ensuring the Government stepped up security measures and redoubled efforts to track down al-Qa'ida "sleepers".
The terrorist network set up by Osama bin Laden is also believed to have received an influx of cash from Saudi supporters in the past few weeks. The money has been pouring in from sympathisers outraged by the Israeli Government's recent assault on Palestinian-held areas, according to intelligence sources.
Although the US-led war on al-Qa'ida and its Taliban protectors in Afghanistan has been largely successful, Ministers admit the terrorist network has been "dug in" in other countries for years and it is continuing to regroup. They also confess the security services are little closer to understanding the chain of events that led to the attacks on America and fear that a complacent public is becoming less vigilant.
One said: "Mr bin Laden might be cornered in a cave but that won't necessarily prevent al-Qa'ida carrying out further attacks. We were pretty shocked at what we heard. The American attacks were five years in the planning. Who knows what could be in the pipeline?"
Ministers have not been presented with any specific evidence of a planned attack in Britain but fear al-Qa'ida "sleepers" could have been in the country for years. They point out some of the men suspected of the US atrocities passed through Britain. Britain's leading role in the coalition in Afghanistan could propel it up the list of targets.
Dr Rohan Gunaratna, an expert on Islamic terrorism, has warned that Mr bin Laden is recruiting support in both Britain and Europe. Mr bin Laden is believed to have written a defiant message posted last month on an al-Qa'ida web site.
Sources believe al-Qa'ida's leadership has been reorganised by Abu Zubaydah, a deputy who escaped from Afghanistan.Reuse content