Image copyright Cabinet Office Image caption Evie, left, and her son Ossie have joined the group of cats trying to keep down the tide of Whitehall mice

The Cabinet Office is the latest government department to turn to cats to try to rid it of its resident mice.

Evie and Ossie, rescue cats from the Celia Hammond Trust, have been given the run of four floors at the Whitehall office.

Downing Street has its own mouser - Larry - who was tasked in 2011 with ridding No 10 of a rat problem.

In April, the Foreign Office took on its own mouser, Palmerston, while the Treasury recruited Gladstone in July.

'Settling in'

Evie and Ossie are the first to come from the Celia Hammond Animal Trust - Larry, Gladstone and Palmerston came from the better-known Battersea Dogs and Cats Home.

Evie is Ossie's mother - a Cabinet Office spokeswoman said the cats would be looked after with donations from staff and were "settling in really well".

Image copyright WPA Pool/Getty Images Image caption Larry stayed at Downing Street when David Cameron left

Much of Whitehall seems to have a rodent problem. Larry was first bought after a rat was spotted scuttling past Downing Street's famous front door on live TV. The Foreign Office and Treasury recruited their own mousers this year.

The Cabinet Office has named Evie after Dame Evelyn Sharp, the first female permanent secretary, while Ossie is named after Sir Edward Osmotherly - author of the rules followed by civil servants in giving evidence to select committees.

A spokesman said the cats had arrived a couple of weeks ago, in time for the 100th anniversary of the creation of the Cabinet Office.

"Everybody's been really enthusiastic. They are a very welcome presence in the office," she said.

"They have been settling in and getting familiar with the building."

The cats will be kept indoors and will have four floors to roam around.