Ukraine’s President Volodymyr Zelensky during his video appearance Saturday at Qatar’s Doha Forum.

Ukraine’s president Volodymyr Zelensky made a video appearance Saturday at Qatar’s Doha Forum, raising the possibility of tactical nuclear weapons being used in the war in Ukraine.

“Russia is deliberating bragging they can destroy with nuclear weapons, not only a certain country but the entire planet,” Zelensky said.

He has also urged Qatar and other energy-rich nations, most notably Saudi Arabia, to boost their production to counteract the loss of Russian energy supplies.

However, it is worth mentioning that Kremlin Spokesperson Dmitry Peskov assured that Russia will not use nuclear weapons in the context of the war in Ukraine unless it faces an "existential threat".

Peskov indicated that "We have a concept of domestic security and it's public, you can read all the reasons for nuclear arms to be used."

"So if it is an existential threat for our country, then it (the nuclear arsenal) can be used in accordance with our concept," he affirmed.

Elsewhere in his remarks at the Doha Forum, Zelensky claimed that “Russia targets civilians in Mariupol and prevents aid from entering.”

Russia has constantly opened humanitarian corridors allowing civilians to leave Mariupol and other Ukrainian cities in routes agreed upon with Ukraine, warning that Mariupol authorities are refusing to give residents the opportunity to pass through humanitarian corridors.

The Ukrainian president warned that the world must face the possibility of food shortages due to war.

“No one is safe from the shocks of food chain disruptions,” he concluded.