Ukrainian Railways CEO Oleksandr Pertsovsky also warned that Russian drone strikes were becoming more precise, complicating Kyiv's ability to fend off incoming attacks.

Russia launched drones at two passenger trains in Ukraine's northeastern Sumy region on Saturday, killing one person and wounding dozens, according to Ukrainian officials.

"We clearly see the intensification of enemy attacks on the railway infrastructure," Pertsovsky told reporters, including AFP.

"There is no military purpose whatsoever," he said.

"The only purpose is to sow panic among people... that the connection will be destroyed and people will be left alone," he added.

Speaking via video call while on a train to Shostka, the station that was hit, he said there had been "40 major attacks" on railway infrastructure since August, "pretty much every other day".

Ukrainian President Volodymyr Zelensky called Saturday's attack, which occurred around 50 kilometres (30 miles) from the Russian border, "savage".

He posted a video showing a mangled train carriage engulfed in flames with twisted metal and busted windows.

"The Russians could not have been unaware that they were striking civilians," he said.

Russia's army has repeatedly targeted Ukraine's railways since invading in February 2022.

Pertsovsky said there had not been a single week of the war without this occurring.

In April 2022, more than 60 people waiting to evacuate the frontline city of Kramatorsk were killed when a Russian missile crashed into the busy station there.

Pertsovsky expressed particular concern about Russian weapons becoming more precise, saying that without effective air defence, "it's unfortunately very easy to imagine that a similar attack could bring way, way worse results".

"They have very precise Shaheds (Iranian-designed drones) that are targeting individual locomotives; they are able also to target energy infrastructure very effectively, making many of the tools that were used for protection ineffective at the moment," he said.

Russia has also stepped up its attacks on Ukraine's energy infrastructure as the weather chills.

Moscow earlier this week launched its largest-ever strike on Ukraine's gas infrastructure, while strikes on Saturday cut off power to some 50,000 households in the northern Chernigiv region.