The United Kingdom and Norway sign a pact to

The United Kingdom and Norway are forming an alliance to “hunt Russian submarines” and protect lines of communication in the North Atlantic Ocean, as part of a new defense agreement between the two countries, the British government announced Thursday.

The agreement will allow the British and Norwegian navies to work side by side. A central element of the agreement is a new joint fleet of anti-submarine warfare ships, in response to a 30% increase in the presence of Russian vessels in UK waters over the past two years, according to the UK announcement. The fleet includes eight British vessels and at least five Norwegian vessels.

“At this time of deep global instability, as more Russian ships are detected in our waters, we must work with international partners to protect our national security,” UK Prime Minister Keir Starmer said in a statement. “This historic agreement with Norway strengthens our ability to protect our borders and the critical infrastructure our nations depend on.”

John Healey, the UK’s defense chief, said the pact, called the Lunna House Agreement, will allow the two countries to “patrol the North Atlantic as one, train together in the Arctic and develop advanced equipment that will keep our citizens safe now and in the future.”

Healey and Tore Sandvik, Norway’s defense chief, signed the agreement in London on Thursday.

The naval alliance will primarily patrol a major maritime region between Greenland, Iceland and the United Kingdom, and monitor the area for Russian activity, the UK government said. In addition to surveillance, the fleet will be tasked with defending the UK’s undersea cables and pipelines, which are responsible for overseas communications, as well as the transport of electricity and gas, and are located in that part of the North Atlantic.

“The agreement provides for closer integration between Norwegian and British forces, cooperation on frigates and joint drone projects in the High North,” the Norwegian Ministry of Defense said.

With the agreement, British forces will also have a greater role in the defense of Norway with a greater presence and more training of British Royal Marines in Norway.

“Both navies will operate as one, sharing maintenance facilities, technology and equipment to create truly interchangeable forces capable of rapidly deploying where needed,” the UK announcement said.

The announcement came as aircrews tracked Russian vessels operating in U.K. waters, including the Russian intelligence ship Yantar, which was spotted several weeks ago at the edge of U.K. maritime territory just north of Scotland, according to British officials.

Starmer welcomed Norwegian leader Jonas Støre to the UK on Thursday, meeting at an air force base in northern Scotland. Starmer said at the base that the UK must “remain alert to the ever-present threat” Russia poses to the country, BBC News reported.