Ukraine cities pounded, Kyiv plays down fallout from leak of US documents

Russian forces pounded frontline cities in eastern Ukraine with air strikes and artillery attacks, while Kyiv played down a report that it is amending some plans for a counter-offensive due to a leak of classified US intelligence documents.

The Russians were using "scorched earth" tactics on Bakhmut, a top Ukrainian military commander said on Monday, as the city in the eastern Donetsk region and other cities and towns came under heavy bombardment.

"The enemy switched to so-called scorched earth tactics from Syria. It is destroying buildings and positions with air strikes and artillery fire," Colonel General Oleksandr Syrskyi, commander of Ukraine's ground forces, said of Bakhmut.

The battle for the small and now largely ruined city on the edge of a chunk of Russian-controlled territory in Donetsk has been the bloodiest of the 13-month war as Moscow tries to inject momentum into its campaign after recent setbacks.

Both sides have suffered heavy casualties in the Bakhmut fighting, but Syrskyi said: "The situation is difficult but controllable."

The head of the Moscow-controlled part of Donetsk, Denis Pushilin, said Russian forces now held 75% of the city, though he cautioned it was too early to talk about Bakhmut's fall.

Moscow's military was also targeting the city of Avdiivka.

"The Russians have turned Avdiivka into a total ruin," said Pavlo Kyrylenko, Donetsk's regional governor, describing an air strike on Monday that destroyed a multi-storey building.

"In total, around 1,800 people remain in Avdiivka, all of whom risk their lives every day."

In Chasiv Yar, the first major town to Bakhmut's west, few buildings remain intact and those queuing for food and other aid do not even flinch at the sound of artillery.

"It used to be scarier, but now we have got used to it," said 50-year-old humanitarian volunteer Maksym. "You don't even pay attention," he added, his words nearly drowned out by the sound of explosions.

As the battles ground on, US broadcaster CNN said Ukraine was forced to amend some military plans ahead of its long-anticipated counter-offensive because of the leak of dozens of secret documents.

US officials are trying to trace the source of the leak, reviewing how they share secrets internally and dealing with the diplomatic fallout.

The documents detail topics such as information on the Ukraine conflict, in which Washington has supplied Kyiv with huge amounts of weapons and led international condemnation of Moscow's invasion.

Asked about the report, Ukrainian presidential aide Mykhailo Podolyak said Kyiv's strategic plans remained unchanged but that specific tactics were always subject to change.

The secretary of the National Security and Defense Council, Oleksiy Danilov, told Reuters: "The opinion of people who have nothing to do with this do not interest us ... The circle of people who possess information is extremely restricted."

Some national security experts and US officials have said they suspect the leaker could be American, but have not ruled out pro-Russian actors.

Kremlin spokesman Dmitry Peskov declined to comment on the leak, but said: "There is in fact a tendency to always blame everything on Russia. It is, in general, a disease."