Ukraine's Zelenskyy warns Russia could use chemical weapons: ‘would like to remind…’

Ukraine President Volodymyr Zelenskyy said that any new package of sanctions against Russia that does not affect oil will be received in Moscow with a smile.

Ukrainian President Volodymyr Zelenskyy on Monday warned that Russia could use chemical weapons in the war-hit country and called on the West to impose tougher sanctions to deter Moscow from such acts. Zelenskyy's warning came amid unconfirmed reports suggesting chemical weapons were used in the southern Ukrainian port of Mariupol.

Ukrainian President Volodymyr Zelenskyy speaks during an address where he says that Russian forces could use chemical weapons. (via Reuters)

"We treat this with the utmost seriousness," Zelenskyy said in his nightly video address.

"I would like to remind world leaders that the possible use of chemical weapons by the Russian military has already been discussed. And already at that time it meant that it was necessary to react to the Russian aggression much harsher and faster."

The Ukrainian President did not say whether chemical weapons had already been used.

An aide to the mayor of Mariupol had said that reports about the chemical attack had not been confirmed and that he would provide details and clarifications later.

Pentagon press secretary John Kirby said the US was aware of the reports but cannot confirm the veracity.

"We cannot confirm at this time and will continue to monitor the situation closely," Kirby said. "These reports, if true, are deeply concerning and reflective of concerns that we have had about Russia's potential to use a variety of riot control agents, including tear gas mixed with chemical agents, in Ukraine."

A Biden administration official, meanwhile, said that the US is providing Ukraine with protective life-saving gear to be used against the possible use of chemical and biological weapons by Russia, reported Reuters. The equipment is being delivered on a rolling basis and some have already been delivered, according to the report.

On Monday, the European Union said that more sanctions on Russia are an option.

"It is time to make this package in such a way that we would not hear even words about weapons of mass destruction from the Russian side," Zelenskyy said. "An oil embargo against Russia is a must. Any new package of sanctions against Russia that does not affect oil will be received in Moscow with a smile."

(With inputs from agencies)