Star Trek actor Sir Patrick Stewart has publicly endorsed cannabis research at Oxford University, after admitting to using the drug for medicinal reasons in America.

Stewart has backed the UK’s first ever research project launched by Oxford University today which aims to explore the benefits of cannabinoid-based medicines for sufferers of arthritis like himself.

Stewart said he uses cannabis sprays, rubs his hands in ointment and swallows pills, all loaded with the substance.

The research, funded by private equity firm Kingsley Capital Partners, will be carried out by Oxford Cannabinoid Technologies, a new company set up to partner with academics from the university.

Stewart said: "I purchased an ointment, spray and edibles. The ointment, while providing some relief from the discomfort, was too greasy to use during daytime and so I only use it at night. It helps with sleep as the pain was reduced.

"I believe that the ointment and spray have significantly reduced the stiffness and pain in my hands. I can make fists, which was not the case before I began this treatment.

“The spray, however, is much more usable and I spray my fingers and particularly my thumb joints several times a day,” he added.

Neil Mahapatra of Kingsley Capital Partners said the partnership with Oxford would “support the development of innovative new therapies to help millions of people around the world”.

It comes after a report published by a cross-party group of MPs and peers called on the government to allow sick people to grow their own cannabis under licence.

The all-party parliamentary group for drug policy reform also wants companies to be allowed to import or grow the drug, and for ministers to strip away legal controls so that medicinal cannabis becomes less regulated than many painkillers.