Russian President Vladimir Putin said Wednesday that Moscow was ready to look for "diplomatic solutions" amid raging tensions with the West over Ukraine but stressed that the country's interests were non-negotiable.

"Our country is always open for direct and honest dialogue, for the search for diplomatic solutions to the most complex problems," Putin said in a video address to mark the Defender of the Fatherland Day, a public holiday in Russia.

But he added: "The interests of Russia, the security of our citizens, are non-negotiable for us."

Putin spoke after parliament's upper house, the Federation Council, on Tuesday gave him unanimous approval to deploy "peacekeepers" to two breakaway Ukrainian regions now recognized by Moscow as independent, and potentially into other parts of Ukraine.

In the video address, Putin congratulated the country's men and said he was certain of the "professionalism" of the Russian military and that they will stand up for the country's national interests. He praised the battle-readiness of the Russian army and said the country would continue to develop state-of-the-art weapons.

"We will continue to develop advanced weapon systems, including hypersonic and those based on new physical principles, and expand the use of advanced digital technologies and elements of artificial intelligence," the Kremlin strongman added. "Such complexes are truly the weapons of the future, which significantly increase the combat potential of our armed forces."

United Nations Secretary General Antonio Guterres has condemned Russia for the escalation in the Ukraine conflict and called for compliance with international law.

"When troops of one country enter the territory of another country without its consent, they are not impartial peacekeepers, they are not peacekeepers at all," Guterres said in New York on Tuesday, in rare open criticism of a U.N. veto power.

Moscow's description of military support for Ukraine's rebel-held regions of Donetsk and Luhansk is a "perversion of the concept of peacekeeping."

In addition, Guterres does not consider the events in eastern Ukraine to be genocide, contrary to what Putin said.

"Genocide is a crime that is clearly defined ... I do not think it is the case (here)," the U.N. chief said.

Guterres called for an immediate cease-fire in eastern Ukraine. "The principles of the U.N. Charter are not an a la carte menu," he said. The crisis is one of the largest global peace and security crises in recent years and a test for the entire international system.

The Ukrainian military said on Wednesday one soldier had been killed and six wounded in shelling by pro-Russian separatists in east Ukraine in the past 24 hours as cease-fire violations remain at a high level.

The military said on its Facebook page it had recorded 96 incidents of shelling by separatists over the past 24 hours compared with 84 a day earlier. It said separatist forces used heavy artillery, mortars and Grad rocket systems.

Ukraine has accused Russia of provoking violence, saying it used it as a pretext to formally recognize eastern Ukraine as independent and move its troops into the region, precipitating a crisis that the West fears could unleash a major war.

Western officials have been warning for weeks that the Russian leader has been preparing an all-out invasion of Ukraine. On Tuesday, U.S. President Joe Biden announced tough new sanctions against Russia for "beginning" an invasion of Ukraine but said there was still time to avoid war.