THE head of the Royal Navy angrily hit back at criticism of his sailors' attempts to rescue a British couple kidnapped by pirates.

First Sea Lord, Admiral Sir Mark Stanhope said reports that the Navy did not do enough to rescue Paul and Rachel Chandler after they were snatched by Somali hostage takers did a "disservice to our sailors".

During a keynote speech on his vision for the future of the armed forces, he insisted his team did a "tremendous job" in its attempts to secure the couple's safety.

He said: "I want to be absolutely clear – this was and remains a hostage situation and for this reason it's not appropriate to discuss specific details.

"[Supply ship RFA] Wave Knight did exactly the right thing. She acted professionally and in accordance with purpose, which was to ensure the safety of Paul and Rachel Chandler.

"I take real issue with some of the emotional and scarlet language used to describe the actions of my sailors.

"The naval service is delivering operational success all over the world in everything from fighting in Afghanistan to search and rescue operations, our sailors are known for working hard and they are working very hard."

Mr Chandler, whose 98-year-old father Alfred Chandler lives in Dartmouth, South Devon, and Mrs Chandler disappeared on October 23 as they sailed from the Seychelles in their 38ft yacht Lynn Rival towards Tanzania. They spoke on camera for the first time last week to warn that their captors were "losing patience" and could kill them within a week.

Admiral Stanhope, speaking at Chatham House in central London, backed the Navy's actions in not forcibly recapturing Mr and Mrs Chandler.

"The sailors did a tremendous job in finding the Chandlers' yacht in the first place but once you have a hostage situation your military options, as most people would understand, are inevitably limited.

"Had there been an opportunity to intervene, while being sure of guaranteeing Paul and Rachel Chandlers' safety, they would have done so.

"The decision not to was undoubtedly the right one."

Sir Mark pointed to Medical Assistant First Class Kate Nesbitt, who received the Military Cross yesterday, as a "shining example" of the service's "bravery and professionalism".

The Navy chief outlined his vision that the country should not lose sight of "conflicts beyond Afghanistan".

He said: "While the focus on Afghanistan, and the priority that has been placed on achieving a successful outcome is unquestionable, we have to appreciate that international frictions do persist elsewhere and the possibility of state-on-state conflict within the next 20 years – either directly involving the UK or, more likely, indirectly affecting our vital national interests – cannot, and must not, be ruled out.

"We in defence are stretched, certainly, but I think we are also delivering across all of our business."

He admitted delivering the service on budget created "an obvious tension".

The Admiral said: "The financial realities are such that the UK is considering adjustments in defence while at the same time the ability of our allies to share the burden of defending our common values may also reduce.

"That creates an obvious tension, and any defence strategy, whatever assumptions underpin it, must reconcile the competing demands of policy and resource."