The tide of public opinion is shifting towards liberalisation of Britain’s drug laws, according to a poll that shows that voters favour the legalisation of cannabis by a margin of two to one.

The YouGov survey found that 48% of adults favour legalisation of recreational marijuana use, up five points in the past year, with just 24% opposed. The figure rises to 52% nationwide for those aged 18 to 49. Support for legalisation in London is even higher, at 56%.

The poll, commissioned by the Conservative Drug Policy Reform Group, suggests a social change is occurring in Britain, which mirrors the change in attitudes that led to the legalisation of same-sex marriage.

It found that support for the legalisation of cannabis runs highest with Labour