Britain said it will sign a major defence deal with Norway on Thursday, building on the Nordic country's 10-billion-pound ($13 billion) purchase of UK warships at a time of heightened threats from Russia.
Norway signed a deal to buy at least five frigates from Britain in September, made by BAE Systems.
The UK said there has been a 30 per cent increase in Russian vessels threatening UK waters in the past two years, and that key underwater cables carrying communications, electricity and gas between the UK and Norway could be at risk.
The deal is to be signed by UK Defence Minister John Healey and Norwegian defence minister Tore O. Sandvik later on Thursday. Under the deal, the two countries will agree their navies can operate side-by-side in the North Atlantic.
Named the Lunna House Agreement after the Scottish headquarters of the Norwegian resistance during the Second World War, the combined fleet of at least 13 British-built Type 26 anti-submarine frigates will be interchangeable.
The UK's deeply unpopular Prime Minister Keir Starmer said the deal would help protect critical infrastructure.
Frigates will patrol seas between Greenland, Iceland and UK, monitoring Russian naval activity, and the two navies will share maintenance facilities, technology and equipment.
The Royal Navy will adopt advanced Norwegian naval strike missiles, and the deal includes deeper collaboration on Sting Ray torpedoes.
The UK will also join Norwegian programme to develop support vessels which will act as motherships for uncrewed mine hunting and undersea warfare systems.
(Reporting by Sarah Young. Editing by Mark Potter)
