LONDON - Several US nuclear bombs have reportedly been delivered to a British air base, marking what is believed to be the first deployment of American nuclear weapons on British soil since 2008, local media reported Tuesday.

The weapons, identified as B61-12 thermonuclear gravity bombs, were flown into RAF Lakenheath, a US-operated base in Suffolk, eastern England, the UK Defence Journal reported on Sunday. The B61-12 is a free-fall nuclear bomb designed to be dropped from aircraft and weighs approximately 320 kg.

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The delivery is believed to have originated from the US Air Force Nuclear Weapons Center in New Mexico and involved the C-17 military transport aircraft, reports said. The aircraft flew with its transponders switched on, making it easily trackable by foreign governments and aviation observers.

Military experts were quoted by The Times as saying that the flight pattern of the US transport aircraft resembled a "one-way drop-off," suggesting a permanent delivery rather than a routine transfer.

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Two US fighter squadrons based at Lakenheath are capable of carrying these bombs using advanced F-35A stealth jets, potentially giving the UK a second nuclear deterrent alongside its fleet of Vanguard-class submarines, the UK Defence Journal said.

Neither the US nor British defense departments have issued any comment on the deployment.

Ahead of the NATO summit held in The Hague in June, British Prime Minister Keir Starmer announced the purchase of at least 12 new F-35A fighter jets from the United States, at a cost of nearly 1 billion pounds (around $1.35 billion).