AGAINST a backdrop of clear blue Middle Eastern skies, HMS Southampton has been powering her way through the sea, leading a war convoy on high security alert.

After leaving Dubai, she rendezvoused with aircraft carrier HMS Illustrious and assault vessel HMS Fearless.

Once in a neat line, this trio of British naval ships moved off into the big, blue yonder, with the city's very own warship leading the way.

The vessels are all part of a fleet deployed to the region in response to the September 11 attacks.

Warships belonging to France, Canada, Japan, Holland, Italy, America and Australia are also in the area.

HMS Southampton's present role is crucial. She is escorting HMS Illustrious.

The destroyer specialises in air defence so she is acting as the aircraft carrier's eyes and ears - and is also poised to defend the entire convoy with her superior fire-power.

The nimble Type-42 can skitter off at a moment's notice to check out a potential problem.

Her hi-tech surveillance equipment is such that she can practically hear a squid sneezing on the bottom of the ocean.

HMS Southampton is also there because she has such an impressive stash of weaponry on board.

The first and most potent line of defence is the Sea Dart, a medium-range anti-aircraft missile, with anti-ship capability.

It can be used to protect the entire convoy and can knock out enemy missiles while they are still way over the horizon.

Another option is the highly-accurate 114mm Vickers Mk8 gun. Automatic, and with an unmanned turret, it is capable of firing a whole range of ammunition to ranges in excess of 15km.

The crew were on a high state of alert, with Operations Room defence watches closely monitoring the sea and skies.

The crew wore flame-resistant clothing and the missiles were kept at several stages closer to launch than normal.

There was a serious mood on board.

Once again the machine guns were manned by sailors clad in metal hats, flash-protection masks and gloves.

Operations Officer Lt Cdr Iain Lower said: "If someone is looking our way we want to come across as very prepared, switched on and ready to take on anything that's going to happen.

"It's a heightened awareness. We're in an area where there could be a group of people who may like to sink HMS Southampton."

The ship hit the Straits, which are a mere 20 miles across at their narrowest point, soon after sunset.

Commanding officer Cdr Gary Doyle was on the bridge for the entire transit.

It was not until the warship made it through the straits in the early hours of Monday that the high alert watch ended.

But there is one consolation for all this hard graft. Because when HMS Illustrious was deployed to Operation Veritas she had to choose which destroyer she wanted at her side. And she plumped for HMS Southampton.

Which is why the city's warship can genuinely claim that she's the "escort of choice".