The UK and Germany have signed a defence pact with the aim of closer co-operation in the face of a growing threat from Russia.

Under the agreement, German submarine-hunting planes will operate from RAF Lossiemouth in Scotland and arms giant Rheinmetall is set to open a factory producing artillery gun barrels using British steel.

The UK-Germany Trinity House Agreement is a sign of the Government’s attempts to forge close relations with European allies, particularly on defence and security measures.

But former defence secretary Sir Ben Wallace questioned its value given Berlin’s continued refusal to send long-range Taurus missiles to Ukraine.

The agreement is the latest sign of Prime Minsiter Sir Keir Starmer’s drive to “reset” relations with the European Union’s key players.

The agreement will see the Nato allies working together on developing long-range strike weapons that can travel further than the UK’s existing Storm Shadow missiles.

And the UK and Germany will also collaborate on developing new land-based and aerial drones.

Defence Secretary John Healey said it was a “landmark agreement”, adding: “It secures unprecedented levels of new co-operation with the German armed forces and industry, bringing benefits to our shared security and prosperity, protecting our shared values and boosting our defence industrial bases.”

Under the agreement, the Ministry of Defence said German P-8 Poseidon maritime patrol aircraft will “periodically” operate out of Lossiemouth in Moray, potentially armed with UK-supplied torpedoes, helping to secure the North Atlantic.

In response to the potential threat from Russian activity at sea, the allies will also work together to protect underwater cables.

In addition, the agreement will pave the way for the new Rheinmetall plant, which will see the UK make artillery gun barrels for the first time in a decade using steel made by Sheffield Forgemasters and supporting 400 jobs.

The first artillery gun barrels are expected to be produced in 2027.

Other measures will see co-operation to strengthen Nato’s eastern flank and extra support for Ukraine, including work on equipping German Sea King helicopters with modern missile systems for use by Kyiv’s forces.

German defence minister Boris Pistorius said: “We must not take security in Europe for granted.

“Russia is waging war against Ukraine, it is increasing its weapons production immensely and has repeatedly launched hybrid attacks on our partners in eastern Europe.

“With the Trinity House Agreement, we are showing that the Nato allies have recognised what these times require and are determined to improve their deterrence and defence capabilities.”

But Conservative former defence secretary Sir Ben suggested the deal was more about cementing links between Labour and German Chancellor Olaf Scholz’s SPD than a step-change in defence co-operation.

He wrote on X, formerly Twitter: “If the new UK/ German ‘Trinity House’ agreement is to mean anything then Germany would have agreed with UK requests to send Taurus to Ukraine AND they would lift any export veto on potential Typhoon sales to Turkey – a Nato member. Otherwise it is pretty hollow and made up of stuff we are already doing or had started.

“This has more to do with ‘SPD is our sister party’ than real military mutual benefit.”