“I have no problem with the medical use of cannabis, just as I have no problem with the medical use of opiates,” Mr Abbott wrote in a letter to talkback radio host Alan Jones dated August 23.

“If a drug is needed for a valid medicinal purpose though and is being administered safely there should be no question of its legality,” he added.

Jones read out the letter from Mr Abbott on his 2GB breakfast programme on Wednesday.

On Monday NSW Premier Mike Baird took to twitter to announce a clinical trial into medical cannabis.

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