Russian drones targeted infrastructure in Ukraine's capital and surrounding areas on Monday, damaging energy facilities and causing some power outages, officials said, as Russia extended its bombardment into the second day of 2023.

Ukrainian forces shot down 45 Iranian-made Shahed drones fired by Russia on the first night of the year, President Volodymyr Zelenskiy said on Sunday, praising Ukrainians for showing gratitude to the troops and one another.

"Drones, missiles, everything else will not help them," he said of the Russians. "Because we stand united. They are united only by fear."

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But in a stern New Year's speech, Russian President Vladimir Putin signaled no let-up in his assault on Ukraine.

By 3 a.m. (0100 GMT), Ukraine's air defence systems destroyed 20 air objects above Kyiv, its military administration said.

"It is loud in the region and in the capital: night drone attacks," Kyiv Governor Oleksiy Kuleba said.

"Russians launched several waves of Shahed drones. Targeting critical infrastructure facilities. Air defence is at work," he said on the Telegram messaging app.

Kyiv Mayor Vitali Klitschko said the strikes had knocked out some power and heating.

"There are emergency power outages in the city," he said on the Telegram messaging app.

Earlier, he said one person was wounded by debris from a destroyed drone that hit a road and damaged a building in a northeastern district of the capital.