HMS Westminster will play a key role in the fight against Colonel Gaddafi by stopping arms entering Libya, a defence expert said.
The Portsmouth-based warship will help enforce a naval blockade as British and allied planes bomb pro-Gaddafi forces.
The Type 23 frigate is joined by Devonport-based HMS Cumberland, medical support vessel RFA Argus and coalition warships.
The naval blockade aims to halt any supplies getting through to pro-regime forces in the west of the country.
Defence expert Eric Grove said: ‘The navy will have a key role to play in Libya. The blockade is quite easy to do but will be significant. There is a chance supporters of the Libyan regime will send arms and supplies to Tripoli to help Gaddafi and this can’t be allowed to happen.’
International forces backed by the United Nations began sea and air assaults on Libyan targets at the weekend.
Royal Navy submarine HMS Triumph joined US warships in firing Tomahawk Land Attack Missiles from the Mediterranean on targeted locations to knock out Gaddafi’s air defence systems.
Prof Grove, who is a professor of naval history at the University of Salford, and an expert in maritime history and strategy, said: ‘It’s good to see the Royal Navy at the forefront like this.
‘The missile strikes have taken out key targets which needed to happen to enforce a no-fly zone.
‘But you need to cut out any chance of Gaddafi making reinforcements. That’s why the blockade will be important.
‘The UN resolution says we can use all necessary means to stop Gaddafi attacking his own people so the ships will be able to make ships stop, search them and turn them back. And if they don’t stop, they may to stop them by force.’
The missile attacks were followed by raids from RAF Tornados and American bombers.
Senior British military spokesman Major General John Lorimer said: ‘We are satisfied our attacks and those of our partners have been highly effective in degrading the Libyan air defence and command and control capability.’
He said Col Gaddafi now appears to be focusing on attacks away from rebel-held city of Benghazi and that western forces will continue the air strikes as Libyan forces loyal to the regime were still violating the ceasefire.
But there was confusion in Whitehall over whether Col Gaddafi himself is a target.
Defence Secretary Liam Fox suggested the dictator could be a ‘legitimate target’ and Downing Street spokesmen insisted it was legal to target anyone killing Libyan civilians.
But armed forces chief, General Sir David Richards, said: ‘Absolutely not. It is not allowed under the UN resolution.’