Palmerston, the UK Foreign Office’s “Chief Mouser” and a social-media “diplocat,” died on February 12, 2026, his official account announced. His age was not disclosed, and the cause of death was undisclosed. The post said he passed away peacefully and would be sorely missed.
A rescue cat adopted from Battersea Dogs and Cats Home, Palmerston worked at the UK Foreign and Commonwealth Office in Whitehall from 2016 to 2020. In a role that is traditionally practical, he became unusually public-facing, appearing in official settings and helping humanize the department’s day-to-day life for a broad audience.
Much of his impact came through social media, where he built an online following of about 105,000 on Twitter/X. When he retired on August 7, 2020, he did so with a resignation-style letter that pointed to enjoying working from home during the coronavirus pandemic and wanting more time away from the limelight. His prominence also made him a regular subject of political-animal coverage, including a noted rivalry with Downing Street’s Chief Mouser, Larry.
Palmerston later moved to Bermuda with Andrew Murdoch after Murdoch became Governor of Bermuda, and was described as a special member of the Government House team. In February 2025, he was announced as returning to duty in a semi-retired capacity as “feline relations consultant.” His lasting legacy is the way the UK Foreign Office used his widely recognized “diplocat” persona to make its work more approachable in public communication.