"I can confirm we have been told that Humphrey sadly died last week some time," a Downing Street spokesman said.

'Chief Mouser'

Official questions were asked in the House of Commons about Humphrey's absence after his departure from Downing Street in 1997.

A Conservative MP demanded proof that the moggy - sometimes given the nickname Chief Mouser to the Cabinet Office - was still alive.

Downing Street said Humphrey had been suffering from a kidney complaint.

The media were later invited to a South London property, where Humphrey was photographed, hostage-style, with copies of the day's newspapers.

He had also gone missing while John Major was in Downing Street.

At the time it was thought he had died.

But he returned after staff at a Westminster medical college read his obituary and realised the cat that had made his way into their building was, in fact, Humphrey.