Momentum appears to be growing for the legalisation of cannabis for medical purposes across Australia.

The push for medicinal cannabis to be legalised nationwide is gathering steam with NSW and Victoria preparing to conduct clinical trials for the drug.

NSW Premier Mike Baird announced on Tuesday that terminally-ill patients would soon be able to use cannabis without fear of being charged in NSW.

The move came as the Victorian government moved to remove barriers to clinical trials of medicinal cannabis.

Mr Baird was moved to act after meeting cancer patient Daniel Haslam, who has been using the drug illegally to relieve his suffering.

“We want to give the terminally-ill, their carers (and) their families greater peace of mind,” Mr Baird told parliament.

“We also want to ensure that carers aren’t forced to watch their loved ones suffer when their pain can be alleviated.”

Mr Haslam’s mother Lucy, a nurse, and his ex-police officer father have been buying cannabis to help their son deal with the side effects of chemotherapy.

Lucy travelled to Sydney from Tamworth in northern NSW,for the announcement.

She told reporters she was “elated” the government had thrown its support behind the medicinal cannabis cause and said she hugged and kissed the premier after he told her the news.

“He’s a very kind and caring man,” Ms Haslam said.

“He’s a dad. Any parent knows the horrible feeling of watching your child suffer and feeling powerless.

“So he can empathise with that I think.”

Ms Haslam described Daniel as a good kid who had never tried the drug before being told in 2010 that he had months to live.

“I guess I was a nurse, my husband was a police officer so we’re not your typical family that uses drugs,” she said.

Her local member, Nationals MP for Tamworth Kevin Anderson, was expected to introduce a private member’s bill this week to legalise medicinal cannabis.

But Mr Baird says there are still concerns about the drug’s supply and distribution.

He has directed a working group to conduct a clinical trial for medicinal cannabis to look at those concerns.

The group is due to report back by the end of 2014.

Under the measures, NSW police will be allowed to exercise discretion not to charge terminally-ill adults who use cannabis.

Opposition Leader John Robertson and the Greens have criticised the measures as weak and a missed opportunity.

Both have been calling for legislative change.

West Australian Health Minister Kim Hames has called for national cannabis trials while Queensland federal MP Warren Entsch is drafting a bill to allow for legal trials of cannabis to treat people with cancer, epilepsy and multiple sclerosis.