Theresa May is being urged to find the "political courage" to drop her opposition to building on green belt land to help tackle the housing crisis.

In a new paper, Simon Clarke, a Tory member of the Commons Treasury select committee, describes progress on building new homes as "painfully slow" and says current restrictions imposed on the buffer zones have become the "central obstacle".

The paper, published by Freer, a new Conservative think tank, proposes relaxing rules on building homes within half a mile of railway stations - areas that are likely to be in "high demand" and are already well served by transport links.

Mr Clarke says his plan would free up land for at least 1.5 million new homes. The proposal is understood to have the backing of several senior ministers.

Mr Clarke's paper comes after Sajid Javid, now the Home Secretary, privately lobbied Philip Hammond to include a similar proposal in last year's Budget.

The move was blocked by Mrs May, whose Maidenhead constituency sits in the green belt surrounding London.

Her aides believe that MPs representing similar areas would resist any relaxation of green belt policy for fear of a backlash among traditional Conservative supporters.