A climate change protester from Brighton who "slimed" Lord Mandelson has been given a caution.

Scotland Yard said Leila Deen attended a central London police station on Thursday and accepted the punishment "on the advice of the Crown Prosecution Service".

The 29-year-old woman, a member of the Plane Stupid campaign group, covered the Business Secretary in green custard as he left a meeting in the capital last month.

Police originally said they would not investigate the matter, but backtracked after former deputy prime minister John Prescott said it would be "totally unacceptable" to allow it to pass unchallenged.

Lord Mandelson was returning to the UK on Thursday following an official trip to meet business leaders in the Middle East.

A spokesman for the Department for Business Enterprise and Regulatory Reform said: "This was a matter for the police."