Putin says power grid strikes response to Crimea drone attack

President Vladimir Putin said Russian strikes on Ukrainian infrastructure and a decision to freeze participation in a Black Sea grain export programme were responses to a drone attack on Moscow's fleet in Crimea that he blamed on Ukraine.

Putin told a news conference on Monday that Ukrainian drones had used the same marine corridors that grain ships transited under the U.N.-brokered deal.

Kyiv has not claimed responsibility for the attack and denies using the grain programme's security corridor for military purposes. The United Nations said no grain ships were using the Black Sea route on Saturday when Russia said its vessels in Crimea were attacked.

Meanwhile, on the 250th day of a war that has ground on since Russia's invasion of Ukraine on February 24, Russian missiles rained down across the country. Explosions boomed out in Kyiv, sending black smoke into the sky.

Russian forces shelled infrastructure in at least six Ukrainian regions on Monday, the General Staff of the Ukrainian Armed Forces said in a statement on Facebook.

"That's not all we could have done," Putin said at the televised news conference, indicating more action could follow.

Ukrainian officials said energy infrastructure, including hydro-electric dams, was hit, knocking out power, heat and water supplies.

Oleh Synehubov, the governor of the northeastern Kharkiv region, said on Telegram that about 140,000 residents were without power after the attacks, including about 50,000 residents of Kharkiv city, the second largest city in Ukraine.

Ukraine's military said it had shot down 44 of 50 Russian missiles. But strikes left 80 per cent of Kyiv without running water, authorities said. Ukrainian police said 13 people were injured in the latest attacks.