Two men have been arrested on suspicion of plotting to kill the Prime Minister by using a bomb disguised as a bag to blow off the gates of Downing Street and then attack her with knives.

The suspects were detained during raids in London and Birmingham last week and charged with terrorism offences. They are due to appear in Westminster Magistrates' Court on Wednesday.

The plot was revealed to the Cabinet yesterday by Andrew Parker, the head of MI5.

Mr Parker also told ministers that security services have foiled nine terrorist attacks in the last year.