Whitehall has drawn up plans to deal with terrorist attacks on British embassies and passenger cruise ships.
Although the Foreign Office insists there has been no specific threat to British passengers on cruise ships or to embassies abroad, officials recently held a crisis planning exercise in which these two scenarios were played out.
The aim was to prepare staff for the possibility of British citizens being targeted by extremist groups and to test new rapid-deployment teams, set up after the Bali bomb blast and first used in the aftermath of terrorist attacks in Saudi Arabia.
Called Blue Monday, the training session - led by senior civil servants and attended by staff and observers from around the world - was held several weeks ago in the Foreign Office's grand Locarno Room. Further exercises are planned.
Whitehall sources said the embassy and cruise ship scenarios were "not selected because we deemed they had a greater risk than any other ones". They were "just examples".
Security has, however, been tightened both at embassies and on cruise ships to deal with the post-11 September terror threat.
Though terrorist attacks on cruise ships are rare, the authorities are determined there will be no repeat of the 1985 incident on the Achille Lauro cruise ship in which Palestinian hijackers killed an elderly American, Leon Klinghoffer, in his wheelchair and threw his body overboard.
Cunard, the cruise line that runs the emblematic QE2, said security had been stepped up "quite considerably".Reuse content