Sybil the cat, who moved into Downing Street shortly after Prime Minister Gordon Brown took office two years ago, has died after a short illness.
The black and white feline, named after Basil Fawlty's wife in the hit 1970s comedy Fawlty Towers, was brought to London by Alistair Darling after he became Chancellor of the Exchequer in Brown's government in June 2007.
Sybil died earlier this week at the home of a family friend, a Downing Street spokesman said.
"Mew Labour is dead," quipped the Independent daily, referring to the fact that Sybil was the first new cat in Downing Street since Tony Blair took power in 1997, after famously rebranding his party as New Labour.
Sybil's arrival was inauspicious, it noted: weeks after she arrived, Darling was grappling with the first run on a bank in over a century at the Northern Rock, presaging last year's full-blown global financial crisis.
Darling's official residence is number 11, next door to Brown's 10 Downing Street home, but a spokesman for the incoming premier admitted in 2007 that the cat would have the run of both houses.
"It's quite difficult to confine cats, so, yes. The prime minister doesn't have a problem with it. (The prime minister's wife) Sarah Brown doesn't have a problem with it," he said at the time.
Sybil's predecessor as chief mouser in the seat of government was Humphrey, who arrived in 1989 when Margaret Thatcher was in office, but left shortly after Blair came to power.