The United Kingdom has announced its plans to expand its nuclear arsenal, from the originally capped 225 warheads to 260. The announcement from Prime Minister Boris Johnson comes after a long standing period of the U.K. trying to prove their compliance with the Nuclear Non-Proliferation Treaty. The increased limit of warheads would see an expansion of the UGM-133 Trident II submarine launched ballistic missiles, which have been used to arm the U.K. Royal Navy. In addition to the increased warhead limit, the U.K nuclear program in general seems to be in a transitional phase, which will have several implications for nuclear nonproliferation efforts.
The U.K. has been in a transitionary period as of late, as it was announced in February 2020 that the Navy planned to reduce the number of warheads, however still maintaining a push to update the submarine program. The proposed submarine updates would see an estimated $43 billion put towards developing new Dreadnaught class nuclear powered ballistic missile submarines (SSBNs); a shift from the current four Vanguard class SSBNs. The submarine development would not account for the cost needed to reduce warhead capacity, which is worrisome not just for the U.K. defense budget, but for NPT compliance.
The shift from the U.K. represents a move away from the JCPOA and NPT agreements which push for the world nuclear powers to pursue nuclear nonproliferation and slowly decrease their arsenals. Other members of the JCPOA have spoken out against the announcement, including Russia and Iran. Russian officials issued a statement saying the U.K.’s warhead limit increase “harms global stability and strategic security”. Iran followed suite and issued a statement noting Prime Minister Johnson’s hypocrisy, as Johnson had recently expressed concern over the direction of the Iranian nuclear program. The U.K.’s announcement has certainly created a stir amongst the world nuclear powers, but it has also reignited the conversation over NPT compliance. The increase in warhead caps does not indicate nonproliferation cooperation from the U.K. which is especially worrisome as it could potentially impact the efforts of the U.S. and Iran returning to the JCPOA.