Fracking giant Ineos has threatened the National Trust with legal action to allow it explore for shale gas on its land.

The petrochemicals group, which owns and runs the Grangemouth oil refinery, has licences to look for the new fuel across swathes of the UK.

It is currently blocked from carrying out such work in Scotland pending the outcome of the current public consultation on fracking, which some scientists believe is environmentally dangerous.

However, the firm, run by billionaire Jim Ratcliffe, is able to explore potential reserves of the gas south of the border. It wants to do some seismic work at a National Trust property in Nottinghamshire but is being stopped by the charity.

Greenpeace, which campaigns against fracking, yesterday revealed documents showing Ineos Shale, a subsidiary of the Ineos group, has threatened the trust with compulsory access to the land under the Mines (Working Facilities and Support) Act 1966.

Activists from Greenpeace have also obtained emails showing the British Geological Survey, the state watchdog, was complaining to Ineos for citing its name in correspondence with landowners. The Sunday Times revealed that Ineos said it had investigated and denied any bully tactics.

Hannah Martin, Energy campaigner at Greenpeace UK, said: "Landowners, local communities and the UK public are tired of being overpowered on the issue of fracking."

"he added: It is particularly concerning that INEOS appears to be using heavy handed tactics, since they were the biggest winner from the latest licensing round for fracking exploration, with 21 blocks of land across the UK.

One of the world’s biggest manufacturers of chemical and oil products has threatened the National Trust with legal action to force it to allow exploration for shale gas on its land."

The Scottish Government's consultation on fracking - which involves drilling underground and then blasting rock with water mixture at high-pressure to release gas - began last month. A moratorium remains in place on the industry.