David Cameron 'should play EU system hard' on migrant benefits
Iain Duncan Smith has said David Cameron should "play the system hard" to push for a block on benefits for EU migrants.
The prime minister is negotiating with other leaders for changes, ahead of the referendum on Britain's membership of the EU.
The Work and Pensions Secretary is urging Mr Cameron to follow the example set by Lady Thatcher in her negotiations in the 1980s.
James Landale reports.