MPs have been told they are not allowed to get a cat to police the Houses of Parliament for mice, because they can not be trusted to look after it properly.
Figures published today revealed that in 2013 there were 221 mouse sightings on the parliamentary estate, slightly down from 254 in 2012. The cost of pest control (including mice) in 2012-13 was £73,522.12.
But Lib Dem MP John Thurso, who speaks for the Commons authorities, said there were a number of practical problems that prevented parliament from getting a resident cat from Battersea Dogs and Cats Home.
"A cat would be at risk from the 1,748 poisonous bait stations used across the estate to control pest populations," Thurso said.
"There would be no reliable way to stop the cat getting on to the busy roads which surround us, nor of looking after the cat responsibly.
And he said it was also likely that "well-meaning" MPs would feed the cat, "making it unlikely that it would catch mice". He also said the Commons had to think of the effect on people who are allergic to cats.
Thurso made the comments in a written response to Tory MP Anne McIntosh who has been lobbying for the Commons to buy a cat.