Putin says Russia will 'intensify' attacks on Ukraine

President Vladimir Putin said on Monday that Moscow would intensify strikes on military targets in Ukraine, after an unprecedented Ukrainian attack over the weekend on the Russian city of Belgorod.

The attack killed 24 people and left over 100 wounded in Belgorod on Saturday. It came after Moscow launched a large-scale attack on Ukrainian cities.

"We're going to intensify the strikes. No crime against civilians will rest unpunished, that's for certain," Putin said on Monday during a visit to a military hospital.

He said Russia would continue to hit what he called "military installations".

"We are doing that today and tomorrow we will continue doing it," Putin announced, speaking almost two years into Moscow's military offensive in Ukraine.

Meanwhile, Kyiv said Russia had hit targeted the country with a "record" number of drones on New Year's Day.

"What happened in Belgorod is a terrorist act," Putin told wounded Russian soldiers, sitting nearby him in hospital uniforms and sanitary masks.

"There is no other way to call it."

He accused Ukrainian forces of targeting "right in the city centre, where people were walking around, before New Year's Eve" and alleged they had "purposefully hit the civilian population".

The Russian leader said he believed the "strategic initiative" in the drawn-out conflict in Ukraine was on the Russian side.

"In any case, that is how I am being briefed," he said.

Putin also claimed Moscow wanted to end the conflict -- which has dragged on for almost two years -- "as quickly as possible" but "only on our terms", according to Russia's state-run TASS news agency.

He repeated his assertion that Ukraine is being used by the West to "settle its problems" with Russia.