OTTAWA -- The world will be watching for leadership from Canada as officials gather in New York this week for a global forum on drug policy, says Health Minister Jane Philpott.

Philpott will be leading the Canadian delegation to the United Nations General Assembly special session on drugs, the first discussion of its kind in nearly 20 years.

Wednesday's meeting happens to coincide with 4/20 -- an annual celebration of cannabis culture that takes on a different meaning in Canada this year, with the governing Liberals having promised to legalize and regulate the recreational use of pot.

Philpott said Canada is moving to "reset" its approach to marijuana with a public health approach that is rooted in evidence, a shift that she intends to make clear at the meetings.

"We have clearly indicated our plans in terms of marijuana and not only decriminalizing but legalizing, regulating and restricting," she said.

"We believe that is important to do for marijuana. At this point, we are not at a point to go beyond that for other substances, but we will continue to look to the best scientific evidence as we look to make our decisions."

The forum provides Philpott an opportunity to push back against harmful drug policies and to promote health, said Donald MacPherson, the executive director of the Canadian Drug Policy Coalition.

In 1998, the general assembly adopted an action plan that emphasized the need for a "drug-free world" and law enforcement. Critics have argued the so-called "war on drugs" has been ineffective and has undermined public health efforts.

"After a long silence, Canada could once again take a position of principled global leadership on drug policy," MacPherson said.

The meeting in New York comes as Canada is experiencing an increased use of a number of prescription drugs in addition to illicit substances, Philpott said.

"One biggest challenges right now in Canada is the fentanyl problem -- that is one of the areas where we are seeing the most dramatic rises," she said.

"There are other new drugs that have recently come to our attention in the Canadian scene. One is something called W-18 (an opioid) which we are very concerned about. Those are probably some of the biggest concerns on our radar."

Canada needs to improve its data collection and surveillance to fully assess the depth of the problem, citing that shortcoming as one of the reasons why B.C. moved to declare a public health emergency over its struggle with fentanyl.

She added she was not particularly surprised to see B.C. take that approach.

"I am happy to see the leadership that British Columbia is playing on demonstrating their determination to address problematic substance use, whether it be prescription use or otherwise," she said.

Philpott, a physician for more than 30 years, also said work needs to be done to establish better criteria for prescriptions including powerful opioids.

Evidence would suggest there are a limited number of doctors who may be over-prescribing, though it is important not to paint health care practitioners with one brushstroke, she said.

"I think that out of fairness, the vast majority ... are extremely well informed, extremely concerned themselves with making sure that they are prescribing appropriately but there is more work to be done in that area," Philpott said.

"There's more to be done in terms of guidelines that would help avoid over-prescribing and making sure that prescribers have a good understanding of assessing someone's risk for developing an addiction."