The UK Royal Navy’s nuclear-armed ballistic missile submarines will receive an enhanced version of a US-manufactured nuclear warhead, the Federation of American Scientists has said.

About 1,200 US W-76-1 warheads, an enhanced version of the W-76, are being built at the Pantex Plant near Amarillo, Texas, US.

The first W-76-1 UK trials test has been performed at the Weapon Evaluation Test Laboratory (WETL), providing qualification data for the deployment of the warhead.

The enhanced version increases the system’s shelf-life by an additional three decades, until the end of 2040, for deployment on UK and US nuclear-armed ballistic submarines.

The extension also coincides with the UK’s strategic defence review, released last year, which stated that a replacement warhead would not be required until 2030.

Details about which version of the warhead the submarines would carry have not yet been disclosed, according to Global Security Newswire.