The United Kingdom is to purchase 12 F-35A jets, which are capable of carrying nuclear weapons, from the United States.

British Prime Minister Keir Starmer will make the announcement during Wednesday’s NATO summit, as he calls on NATO members to do more to support the alliance.

“The UK’s commitment to NATO is unquestionable, as is the alliance’s contribution to keeping the UK safe and secure,” Starmer will say, according to Downing Street.

“But we must all step up to protect the Euro-Atlantic area for generations to come.”

The announcement follows repeated criticisms by US President Donald Trump that NATO countries are not spending enough on defense.

The fifth-generation fighter aircraft, built primarily by US manufacturer Lockheed Martin, is one of the most advanced fighter jets on the planet – but it is also one of the most expensive.

The decision to acquire aircraft with the capacity to carry nuclear weapons also represents a major strengthening of Britain’s nuclear posture.

It means that in addition of UK’s existing sea-borne nuclear deterrent, the country will also now join NATO’s dual capable aircraft nuclear mission.

“In an era of radical uncertainty we can no longer take peace for granted,” Starmer will say.

According to the British government, the decision will support 20,000 jobs in the F35 program in the UK, with 15% of the global supply chain for the jets based in Britain.