PMQs: Cameron quizzed on lobbying by Margaret Beckett
4 September 2013 Last updated at 13:50 BST
The prime minister said there was a "concerted lobbying campaign being run by the trade unions" against the government bid to reform lobbying.
And David Cameron said Labour did not want the unions "brought within the law" on funding.
Labour's Margaret Beckett had named a range of bodies - including the Salvation Army, Countryside Alliance, British Legion, Oxfam and CoservativeHome - against the changes.