David Cameron has called for the creation of "social enterprise zones" to help the poorest in society.

The Conservative leader used an article in the Guardian to say helping those left behind by rising living standards should be "the most urgent political problem for the British government".

Arguing that central government intervention is often too blunt an instrument to help the poorest families, he endorsed the findings of a Tory policy group which said the solution lay in grassroots entrepreneurship.

He said government programmes lacked "the flexibility, the combination of moral toughness and sensitivity to people's personal circumstances" needed in the most difficult cases, and that the answer lies "in communities themselves, not in well-meaning schemes directed from Whitehall".

"Social enterprises in particular represent a huge potential resource for our most hard-pressed communities," he wrote.

"These are not, as many on the left claim, cut-price welfare organisations, commercial wolves dressed in the sheep's clothing of charity.

"They are fired by the same passion for public service which drives the statutory sector, but they deliver it in a way which is often more effective than the large and lumbering agencies of government."

He said smaller, locally-based voluntary organisations were often losing out to national schemes, and that government failed to take into account the different needs of neighbourhoods within local authority areas.

The zones would give councils the power to create "a radically deregulated environment" for social enterprises and voluntary organisations, with tax relief, fewer planning restrictions and funding from a community bank.

The policy group was headed by former special adviser Rodney Lord and parliamentary candidate Harriett Baldwin.