Image copyright Getty Images Image caption Environmental activists claim fracking can pollute water supplies

Ministers are considering changing trespass laws to make it easier for energy companies to carry out fracking beneath people's homes without permission.

The Department of Energy and Climate Change said it is reviewing whether the existing process is "fit for purpose".

The move comes amid concern that fracking for shale gas could otherwise be held back by lengthy and costly court proceedings.

It will consult on the change.

Fracking - or hydraulic fracturing - is a technique in which water and chemicals are pumped into shale rock at high pressure to extract gas.

Currently operators need to ask homeowners before they drill under their land, but they have a right to appeal by law if an agreement cannot be reached.

"There is an existing legal route by which operators can apply for access where this can't be negotiated. We're currently considering whether this existing route is fit for purpose," said a spokesperson for the Department of Energy and Climate Change.

Shale gas exploration typically involves drilling down vertically and out horizontally, often for more than a mile.

Environmental activists are against the technique, claiming it can increase climate change, cause small earthquakes and pollute water supplies.

However, the government backs fracking saying it believes the potentially large reserves of shale gas could reduce energy bills and create jobs.

Last year Prime Minister David Cameron pledged a "simplified system" for companies to get permission for fracking.