Tommy Chong is having treatment for rectal cancer.

The 77-year-old actor - famed for his cult classic 'Cheech & Chong' 'stoner' films, also starring Cheech Marin - has been told he has cancer for the second time and has admitted he is using marijuana ''like crazy'' for relief like he did the last time.

He told Us Weekly magazine: ''I've had some medical issues lately. I got diagnosed with rectal cancer.''

In 2012, Chong underwent treatment for prostate cancer and used the illegal herbal drug to aid his recovery.

He added: ''I'm using cannabis like crazy now, more so than ever before. I'm in treatment now. I've been - just the case either way, either I get healed or I don't. But either way, I'm going to make sure I get a little edge off or put up.''

Chong is known for voicing his opinions on legalising cannabis to help counteract the pain.

He once said of his use of the drug: ''I've got prostate cancer, and I'm treating it with hemp oil, with cannabis. So (legalising marijuana) means a lot more to me than just being able to smoke a joint without being arrested.''