The United Kingdom has confirmed that it is developing a replacement UK sovereign nuclear warhead for its Trident missiles. The Ministry of Defence says in the ‘Defence Nuclear Enterprise Command Paper’ that “Replacing the UK’s warhead will ensure the UK’s deterrent remains cutting-edge, safe and effective”.

In the paper released today, they state:

“The UK committed to replacing our sovereign warhead in parliament in February 2021. Using modern and innovative developments in science, engineering, manufacturing and production at AWE, we will ensure the UK maintains an effective deterrent for as long as required.

The Replacement Warhead Programme has been designated the A21/Mk7 (also known as Astraea). It is being delivered in parallel with the US W93/Mk7 warhead and each nation is developing a sovereign design. This will be the first UK warhead developed in an era where we no longer test our weapons underground, upholding our voluntary moratorium on nuclear weapon test explosions.

...

For those unaware, the Trident II D5 missile is manufactured in the US. It comprises the missiles and supporting systems fitted on the submarine as well as training and shore support equipment.

Under the agreement with the United States, the UK accesses a shared missile pool. Missiles are loaded into our submarines in Kings Bay, Georgia, US. The UK-manufactured warheads are mated to the missiles at HMNB Clyde.