More than two-thirds of Australians back the use of medicinal cannabis, according to a new survey likely to bolster support among MPs and senators who are set to vote on the issue in the coming months.

Palliative Care Australia has found 67 per cent of people are happy to see the drug used to help patients with chronic pain and illness – and support is strongest among the elderly.

"I have no problem with the medical use of cannabis just as I have no problem with the medical use of opiates": Tony Abbott. Credit:Alex Ellinghausen

The survey found people in older age brackets were more supportive of legalisation than the young: 72 per cent of 75 to 84-year-olds are in favour, compared to 62 per cent of 18 to 24-year-olds.

The survey of 1006 people from across the country found just 9 per cent of Australians oppose the use of medicinal cannabis. About a quarter – 24 per cent – say they are not sure.