The United States has not confirmed the use of chemical weapons in Mariupol, but had previously warned the Ukrainians that Russia could use chemical agents in the southeastern Ukrainian city, State Department spokesperson Ned Price told CNN.

“Before today, there was credible information available to us that the Russians may have been preparing to use agents, chemical agents, potentially tear gas mixed with other agents, as part of an effort to weaken, to incapacitate the Ukrainian military and civilian elements that are entrenched in Mariupol, using these agents as part of an effort to weaken those defenses”, - Price said.

“We shared that information with our Ukrainian partners. We are going to be in direct conversations with them to try and determine what exactly has transpired here, and as soon as we gain additional fidelity, we’ll be in a better position to say what this was or what this may have been”, - he said.