Yes, prime mouser

The official title of Chief Mouser to the Cabinet Office is held by a cat in charge of keeping mice under control at the UK Prime Minister's office at 10 Downing Street. The current incumbent is Larry.10 Downing Street. History of the UK Government. UK Government (2015).

It was once commonplace to employ cats as mousers, so Larry is not unique; the UK Post Office, for example, employed a cat named Tibs the Great for many years.The Post Office Cats 150. The Postal Museum. Gavin Guffie (2018-09-18).