"...it has been reported by the Observer today, that one of the man suspected of involvement in the attacks in London on the 7th July was being kept under surveillance by the British security services."
It appears that authorities had suspicions about at least one of the men, which could lend credance to the French claims. Also, if the men had been taken in by authorities, and then were released in order to "break a wider network", then authorities certainly would not make that public, in order to protect both their sources, and themselves.
The men may not have been arrested, but it certainly appears to be the case that there was an intelligence gathering process involving at least one of the men.
Which leads us neatly to why Charles Clarke would want to deny that any of those involved had been under suspicion of terrorist related activities previously.
If it turned out that ALL 4 men were supposedly informants (as some of the Madrid bombing suspects turned out to be) then this is a huge failure by authorities, and also lends weight to the claims that Benjamin Netanyahu received some sort of warning prior to the explosions in London.
These are important questions, not so called "conspiracy theories", and Blair & Co need to now answer these questions truthfully.
If the French claims are proved to be correct, then Clarke needs to resign.
Now, we have this report, from Newsweek, which confirms that 2 of those involved with the 7th July London bombings were under surveillance, and it is quite possible that a 3rd was under surveillance:
In an official document examined by NEWSWEEK, a British judge reports that U.K. investigators had pictures and voice recordings of Mohammed Siddique Khan—believed to have been the plot leader—and another suicide bomber, Shahzad Tanweer, meeting several times in February and March 2004 with suspects in an earlier, separate terror plot that U.K. authorities investigated under the code name Operation Crevice.
This report adds further weight to the French claims that 2 "terrorist suspects" were released by British authorities in order to "break a wider network." It is long past time for an explanation by Charles Clarke, and, it seems, his resignation.