US President Joe Biden has said the United States will not provide the F-16 fighter jets that Ukraine has sought in its battle against Russia.

Biden's comment came shortly after Ukrainian President Volodymyr Zelenskyy said Russia had begun exacting its revenge for Ukraine's resistance to its invasion with relentless attacks in the east.

Just last week, Ukraine won a huge boost after the United States and Germany announced plans to provide heavy tanks to the country.

Meanwhile, the Russian forces have claimed a series of incremental gains in the east of Ukraine.

Weapons Yet To Reach Ukraine

Zelenskyy is urging the West to hasten the delivery of its promised weapons so Ukraine can go on the offensive. According to reports, the hundreds of modern tanks and armoured vehicles pledged to Ukraine by Western countries in recent weeks are months away from delivery.

This leaves Kyiv to fight through the winter in what both sides have described as a meat grinder of relentless attritional warfare.

Moscow's Wagner mercenary force has sent thousands of convicts recruited from Russian prisons into battle around Bakhmut, buying time for Russia's regular military to reconstitute units with hundreds of thousands of reservists.

Russia Continues Shelling

The Russian invasion of Ukraine, which Moscow justifies as necessary to protect itself from its neighbour's ties with the West, has killed tens of thousands of people and driven millions from their homes.

According to Ukrainian military analyst Oleh Zhdanov, the country still holds control of Maryinka and Vuhledar.

Ukrainian servicemen ride atop an infantry fighting vehicle along a road (Photo: Reuters)

Over the past 24 hours, Russian forces shelled a dozen settlements in the Bakhmut sector. Trained tank, mortar and artillery fire were witnessed in towns near Avdiivka to the south.

In the central Zaporizhzhia region and in the southern Kherson region, Russian forces shelled more than 40 settlements.

In Kherson, the Russians shelled towns on the left bank of the Dnipro River that they abandoned in November, Kyiv said.

Targets included the city of Kherson, where there were casualties.

Meanwhile, Zhdanov said Ukrainian forces repelled Russian attempts to advance on a number of towns and villages in the Donetsk region.

The front line in the sector has not changed, he said.

Talking to reporters, Zelenskyy said Russian attacks in the east were relentless despite heavy casualties on the Russian side, casting the assaults as payback for Ukraine's success in pushing Russian forces back from the capital, northeast and south earlier in the conflict.