KYIV - Kyiv launched one of the biggest drone attacks on Russia since the full-scale war began, targeting power plants and an oil refinery overnight, while Moscow's forces made further advances towards a key town in eastern Ukraine, officials said on Sunday.

Ukraine also reported Russian shelling of areas near their shared border. A missile attack on a grain convoy killed a truck driver while another, on Ukraine's second largest city of Kharkiv in the northeast, injured at least 28, it said.

The fighting comes at a critical juncture in the two-and-a-half year conflict, with Russia pressing an offensive in eastern Ukraine while trying to expel Ukrainian forces that broke through its western border in a surprise incursion on Aug. 6.

Russia last week pounded Ukraine with its heaviest air strikes of the war, hitting energy facilities, part of a campaign of drone and missile barrages that have killed thousands of civilians and troops since the conflict began in February 2022.

Ukraine, with a rapidly expanding domestic drone industry, has stepped up its own attacks on Russian energy, military and transport infrastructure.

It is also pressing the United States and other allies for permission to use more powerful Western-supplied weapons to inflict greater damage inside Russia and impair Moscow's abilities to attack Ukraine.

Russian officials said air defence units had destroyed 158 drones launched by Ukraine overnight, and that debris caused fires at the Moscow Oil Refinery and at the Konakovo Power Station in the neighbouring Tver region.

Temporary restrictions imposed on Moscow's Vnukovo, Domodedovo and Zhukovsky airports overnight were lifted on Sunday morning, according to aviation watchdog Rosaviatsia.

Reuters could not independently verify the reports of drone attacks against Russia or from the battlefield in Ukraine, and Kyiv has yet to comment. Russia rarely discloses the full extent of damage inflicted by Ukraine's air attacks.

RUSSIA ADVANCES IN DONETSK

Ukrainian President Volodymyr Zelenskiy said that last week alone Russia had used 160 missiles, 780 guided aerial bombs and 400 attack drones against cities and troops across Ukraine, and he again called for permission to use Western-supplied weapons to strike deep inside Russia.

"To give full defence and secure our cities from this aggression, more support is needed for a just Ukrainian response," he said on Telegram on Sunday.

Zelenskiy called for "a decision on long-range strikes on missile launch sites from Russia, destruction of Russian military logistics, joint shooting down of missiles and drones".

Senior Ukrainian officials were in Washington last week to further push their case. Kyiv's allies are wary of how Russian President Vladimir Putin would respond should their weapons be used against targets far inside Russian territory.

The pleas come as Russia accelerates its advances towards the eastern Ukrainian town of Pokrovsk, which is a vital military hub and transport link to towns and cities further north.

Ukraine had hoped that its surprise incursion into Russia's Kursk region launched last month would force Russia to re-deploy troops and take the pressure off besieged forces in the east, but so far it does not appear to have had the desired effect.

Russia's defence ministry said on Sunday its forces had captured two more settlements in Donetsk region, including Ptyche, just 21 km (13 miles) southeast of Pokrovsk, and were "continuing to advance deep into the enemy defences". Russian forces also seized the settlement of Vyimka, it said.

Ukraine's top commander Oleksandr Syrskyi said the situation was "difficult" around Russia's main line of attack in eastern Ukraine, but that all necessary decisions were being taken.

In Kharkiv, Mayor Ihor Terekhov said 28 people had been injured in a Russian air attack. Regional governor Oleh Syniehubov said they included a six-year-old child and two medics.

  - Reuters