Russian forces attacked Ukraine's Kyiv and Odesa regions with Iranian-made drones and used missiles to strike other areas, Ukrainian officials said as Moscow punished the country for a fourth day after a truck bomb damaged a bridge to the annexed Crimean Peninsula.

A strike carried out near Makariv, a small city located 50km west of Kyiv, destroyed critical infrastructure. Throughout the capital region, residents whose lives had resumed some normalcy when the war moved east months ago again awoke to air raid sirens.

Russia intensified its bombardment of civilian areas in recent weeks as its military lost ground in multiple occupied regions of Ukraine that President Vladimir Putin illegally claimed as Russian territory. Putin's supporters urged him to escalate the campaign further after the Crimea bridge attack.

It wasn't clear whether the explosive-packed drones caused any casualties. Ukrainian officials said dozens of people died this week after the Russian military ramped up the scope of its attacks, including at least two killed Thursday in a missile strike that destroyed an apartment building in southern Ukraine.

Damage to a power station in Kyiv, Ukraine after a Russian attack. Photo / Maxar Technologies via AP

Ukrainian officials said Thursday that Iranians in Russian-occupied territories of Ukraine were training Russians how to use the Shahed-136 systems, which can conduct air-to-surface attacks, electronic warfare and targeting. Their deployment may indicate the Russian military is running out of its own drones.

The low-flying aerial devices help keep Ukraine's cities on edge, but the British Defence Ministry has said the Iran-made drones were unlikely to be fulfilling their purpose of providing strike options deep into Ukrainian territory, with many reportedly destroyed before they hit their targets.

Ukraine's air force command said Thursday its air defence shot down six Iranian drones from over the Odesa and Mykolaiv regions during the night.

The Russian military resumed widespread attacks in Ukraine on Monday following the weekend explosion that damaged the Kerch Bridge. The 19km span holds importance as a symbol of Moscow's power and carries military supplies from Crimea, which Russia annexed from Ukraine in 2014.

A Ukrainian serviceman checks the trenches dug by Russian soldiers in a retaken area in Kherson region. Photo / Leo Correa, AP

The speaker of Russia's lower house of parliament said Russian forces struck more than 70 energy facilities in Ukraine this week. He threatened an "even tougher" response to future attacks by "the Kyiv regime", although Ukraine has not claimed responsibility for the bridge bombing.

"All the organisers and perpetrators of the terrorist attacks must be found; those who resist must be destroyed," State Duma speaker Vyacheslav Volodin wrote on Telegram.

Russian officials said Thursday that Ukrainian forces shelled Russia's Belgorod region that borders Ukraine. According to the region's governor Vyacheslav Gladkov, the shelling damaged a multi-story residential building in the city of Belgorod, while a projectile that landed on a school sports ground did not explode.

Putin said the massive barrage of missile strikes across Ukraine that started Monday was retaliation for what he called Kyiv's "terrorist" actions targeting the Kerch Bridge. Putin vowed a "tough" and "proportionate" response to Ukrainian attacks that threatened Russia's security.

Kyiv was hit at least four times during Monday's strikes, which killed at least 19 people and wounded more than 100 across the country.

A man rides his motorcycle past a destroyed car in the retaken village of Velyka Oleksandrivka. Photo / Leo Correa, AP

Russian forces have made early morning attacks a daily occurrence in southern Ukraine as the Ukrainian military wages a counteroffensive aimed at recapturing occupied areas.

In the southern city of Mykolaiv, overnight shelling destroyed a five-story apartment building as fighting continued along Ukraine's southern front. The Mykolaiv regional governor, Vitaliy Kim, said an 11-year-old boy was pulled from the rubble after six hours and rescue teams were searching for seven more people.

Kim said the building was hit by an S-300 missile, a type ordinarily used for targeting military aircraft but the Russian military appears to be increasingly using for imprecise ground strikes.

Some Nato allies this week pledged to send advanced weapons to Ukraine, including air defence systems that the government in Kyiv has said are critical to defeating the invading Russian forces.

Britain said Thursday it would provide missiles for advanced NASAM anti-aircraft systems that the Pentagon plans to send to Ukraine in coming weeks. It's also sending hundreds of additional aerial drones for information gathering and logistics support, plus 18 more howitzer artillery guns.

"These weapons will help Ukraine defend its skies from attacks and strengthen their overall missile defense alongside the US NASAMS," UK Defense Secretary Ben Wallace said.

The systems, which Kyiv has long wanted, are designed to provide medium- to long-range defence against missile attacks.

The pledge came as Nato defence ministers led a meeting in Brussels of the Western military alliance's secretive Nuclear Planning Group. Nato plans to hold a nuclear exercise next week amid concerns over Putin's insistence he would use any means necessary to defend Russian territory, including the illegally annexed regions of Ukraine.

Nato is keeping a wary eye on Russia's movements but has so far seen no change in its nuclear posture. Russia is expected to hold its own nuclear exercises soon, possibly at the same time as Nato or just after, according to Nato diplomats.

Putin met Thursday with Turkish President Recep Tayyip Erdogan on the sidelines of a regional summit in Astana, Kazakhstan. UN officials expressed hope a day earlier that the meeting would lead to an extension of agreements that led to the resumption of Ukrainian grain exports and allow Russia to ship fertilisers.

"We are determined to transport Russia's grain and fertiliser to underdeveloped countries through Turkey," Erdogan said, adding that Ankara and Moscow could jointly designate the countries the products would go to.

The war in Ukraine has created food shortages and price increases by slowing shipments of agricultural products.

- Sabra Ayres, AP