David Cameron warned about EU freedom of movement

David Cameron has been warned, repeatedly, by some fellow European leaders not to try to change the rules on freedom of movement within the EU.

Mr Cameron has been pressing for change to tackle migration levels to the UK.

But no fewer than three prime ministers - from Finland, Sweden and Norway - have insisted that freedom of movement is a fundamental principle of the European Union which cannot be undermined.

The BBC's political editor Nick Robinson reports.