Deputy Prime Minister Nick Clegg has backed calls for a royal commission to consider decriminalising illegal drugs, despite opposition from David Cameron.

The PM has rejected the Home Affairs Select Committee's report highlighting Portugal's approach, where people found with drugs are not always prosecuted.

But Mr Clegg told the BBC the government needed to be open-minded and look at alternative approaches.

Mr Cameron said he was "entirely entitled to take a view" on the matter.

Mr Clegg said different politicians of different parties were entitled to take a different view on "how we have another look at how we deal with drugs".