While Ukraine is talking about a burgeoning counteroffensive, Russian U.K. Ambassador Andrey Kelin is warning about a "new dimension" coming to the war in Ukraine.

Russia "hasn't just started yet to act very seriously," Kelin told the BBC on Saturday. "Russia is 16 times bigger than Ukraine. We have enormous resources."

Kelin added the warning that NATO support for Ukraine, particularly the U.K., is going to lead to an escalation.

The war is in year two after Russia's Vladimir Putin "special military operation" began in February 2022 and its duration "depends on the efforts in escalation of war that is being undertaken by NATO countries, especially by the U.K.," Kelin told BBC.

"Sooner or later, of course, this escalation may get a new dimension, which we do not need, and we do not want. We can make peace tomorrow."

Russian Security Council Deputy Chair Dmitry Medvedev earlier this week, though, poured cold water on a peace deal with Ukraine's Volodymyr Zelenskyy.

"This conflict will last for a very long time — for decades, probably — this is a new reality," Medvedev said, according to Russian news agencies, adding talks with "the clown Zelenskyy" were impossible.

"Everything always ends in negotiations, and this is inevitable, but as long as these people are in power, the situation for Russia will not change in terms of negotiations," Medvedev added.

"There are irreversible laws of war. If it comes to nuclear weapons, there will have to be a pre-emptive strike."

Medvedev added a warning of nuclear war and delivering "a missile with a nuclear charge coming to them."

"The Anglo-Saxons do not fully realize this and believe that it will not come to this: It will under certain conditions," Medvedev concluded.

Information from Reuters was used in this report.

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