Deputy Prime Minister Nick Clegg said:
"The first duty of any government is to keep the public safe and the committee that's looked at the Home Office proposals say there is a problem and we need to do something about it. I agree with them.
"But we equally have a duty to make sure that we do that in a way which doesn't lead to unnecessary or excessive snooping on people's emails and telephone calls.
"The committee has said the proposals as they're presently drafted are over the top in important respects, not workable in other respects and possibly very expensive for British taxpayers.
"That's why we now need a fundamental rethink, go back to the drawing board and come back with proposals where we get the balance right."