The presence of both Ukrainian President Volodymyr Zelenskyy and a potential high-level representative from the Russian government at this week's United Nations General Assembly will be a challenging but necessary event, Canada's UN ambassador says.

Zelenskyy is scheduled to speak in-person for the first time before the in New York City on Tuesday more than a year and a half after Russia invaded Ukraine.

Speaking to CTV's Question Period host Vassy Kapelos in an interview airing Sunday, Ambassador Bob Rae said he understands that the UN Security Council, of which Russia is a permanent member, is looking to organize a meeting with Zelenskyy.

Russian Foreign Minister Sergey Lavrov also may attend the General Assembly.

"I mean, it'll obviously be a moment of high drama," Rae said.

"There's talk that Foreign Minister Lavrov will be going and that's no surprise. He comes regularly to the UN. It'll be challenging, but it's necessary to hear what they have to say and to get a sense of how this public debate will unfold through the winter and into next year."

It comes after meetings between Russian President Vladimir Putin and North Korean leader Kim Jong Un, which some speculate could lead to Pyongyang supplying Moscow with ammunition for its war efforts in Ukraine.

The European Union on Friday decided not to renew its ban on Ukrainian grain to nearby countries, an issue those nations say threatens the livelihoods of their own farmers. Russia in July pulled out of an UN-brokered deal allowing Ukraine to ship grain safely through the Black Sea.

And a recent meeting of the G20 saw the group of top world economies soften its language on the war in Ukraine.

Zelenskyy's address to the General Assembly could make a difference as far as appealing to the countries that make up the so-called , Rae said.

This would include India, which hosted the recent G20 meeting and has abstained from UN resolutions demanding Russia end its invasion. India has adopted a neutral stance over the war and called for diplomacy.

"We've been encouraging the Ukrainians to engage in as much global diplomacy as they can," Rae said.

"The challenge actually, really, is that there's the Russian aggression. There's also the impact of the war on the global economy and after the pandemic when many countries were very hard hit … climate change having a strong impact on developing countries. This effect on food prices, on gasoline prices, energy prices, even on food security and food availability, has been very, very dramatic.

"… The reality is that this is a war that's about fundamentally about the future life of Ukraine. Ukraine is fighting for its life. So, I think it's a message that the whole assembly needs to hear."

With files from The Associated Press