Russian President Vladimir Putin said Wednesday he was introducing martial law in four Russian-occupied regions of Ukraine that Moscow last month claimed as its own territory.

In televised remarks to members of his Security Council, Putin also instructed the government to set up a special coordinating council under Prime Minister Mikhail Mishustin to work with Russia's regions to boost Moscow's war effort in Ukraine.

The moves, nearly eight months into the war, marked the latest escalation by Putin to counter a series of major defeats at the hands of Ukrainian forces since the start of September.

They came on the same day that Russian-installed officials in Kherson, one of the four occupied regions, told civilians to leave some areas as soon as possible in anticipation of an imminent Ukrainian attack.

Putin said the measures he was ordering would increase the stability of the economy, industry and production in support of what Russia calls its special military operation.

"We are working on solving very complex, large-scale tasks to ensure a reliable future for Russia, the future of our people," he said.