Government adviser Eric Carlin has resigned from the Advisory Council on the Misuse of Drugs, (ACMD) following unease about the speed with which Mephedrone was criminalised.

Mr Carlin said the decision to criminalise the drug taken earlier this week was "unduly based on media and political pressure".

He is the latest member of the ACMD to resign following the sacking of former chairman Professor David Nutt.

Earlier this week Home Secretary Alan Johnson announced the dance drug Mephedrone would be banned within weeks.

The legal high, which has been linked to up to 25 deaths in England and Scotland, will be banned and made a Class B drug.

Mr Carlin, speaking from Brussels, said he believed the decision to rush through the ban had been politically motivated in order for the Government to look tough prior to the election.