Russia plans to "exhaust" Ukraine with Iranian-made drone attacks, President Volodymyr Zelensky says, as quoted by the BBC.

It has been accused of launching waves of so-called "kamikaze" drones at Ukrainian cities and power plants in recent months.

What is the Russian "kamikaze" drone?
The Ukrainian government and Western intelligence agencies say Russia has been using Iranian Shahed-136 drones (Wikipedia) in the conflict since last fall.

Also called Geranium-2 by Russia, it has explosives in its nose warhead and is designed to steal over a target until instructed to attack.

The Shahed-136 has a wingspan of about 2.5 m (8.2 ft) and can be difficult to detect on radar.

Iran's government claims it supplied a "small number" of drones to Russia before the war. But the US and the European Union have accused Iran of sending regular supplies of drones to Russia, and the EU has imposed sanctions in response.

What damage have kamikaze drones done in Ukraine?
Russia was first reported to have used a Shahed-136 drone on September 13, attacking military targets in the Kharkiv region in the east of the country.

Since then, Russia has repeatedly attacked both military and civilian targets in the Kyiv, Odesa and Mykolaiv region with drones.

Ukraine claims Russia shot down more than 80 Iranian Shahed drones on January 1 and 2, but says it shot down all of them.

Russia often targets power plants to deprive the Ukrainian population of electricity and heating during the winter months.

How is Ukraine trying to fight them?
Ukrainian armed forces have used small arms, heavy machine guns, portable anti-aircraft missiles and electronic jamming devices to try to shoot down drones.

This can be difficult when shipping in large quantities or "swarms".

However, Ukraine claims that its air defenses have been able to shoot down over 80% of all the drones that Russia has sent against it.