Geoff Hoon was told yesterday that TA soldiers did not sign up in order to "defend Heathrow".

The criticism came as the defence secretary put forward plans to make greater use of the TA in defending the security of key installations in the UK.

The Tories yesterday called on the government to restore the TA to its former strength.

Hoon signalled that he believes that the UK's full-time forces should play a greater role in targeting terror cells abroad.