The Saudi announcement of the arrests came just over a week after security services in Morocco said that they had detained three Saudi citizens, who they said were al-Qaeda members, for plotting to attack NATO warships in the Strait of Gibraltar.

ECONOMIST: A clear and present danger | The

Germany, which abstained on the UN resolution authorising the mission, went so far as to withdraw its crews from NATO warning and control aircraft and its warships from other NATO missions in the Mediterranean.

ECONOMIST: The future of the transatlantic alliance

Nato air strikes have hit eight warships belonging to Col Muammar Gaddafi's forces in co-ordinated raids on Tripoli, Al Khums and Sirte.

BBC: Libya: Nato strikes hit eight Gaddafi warships in ports

"All the vessels targeted last night were naval warships with no civilian utility, " said Rear-Adm Russell Harding, Deputy Commander of Nato's mission in Libya.

BBC: Libya: Nato strikes hit eight Gaddafi warships in ports