KYIV  - President Volodymyr Zelenskiy accused Russia on Friday of committing war crimes in Ukraine's northeast and said it was too early to say the tide of the war was turning despite rapid territorial gains by his forces this month.

The Ukrainian leader also told Reuters in an interview that the outcome of the war with Russia, now in its seventh month, hinged on the swift delivery of foreign weapons to his country.

He compared the situation in newly liberated areas of the northeast "to the bloody soap opera after Bucha", a town near Kyiv where he accused Russian forces of committing numerous war crimes in the first phase of the war. Moscow denied the charges.

"As of today, there are 450 dead people, buried (in the northeastern Kharkiv region). But there are others, separate burials of many people. Tortured people. Entire families in certain territories," Zelenskiy said.

Asked if there was evidence of war crimes, he said: "All this is there... There is some evidence, and assessments are being conducted, Ukrainian and international, and this is very important for us, for the world to recognise this."

The Kremlin did not immediately respond to a request for comment on Zelenskiy's new allegations.

Russia regularly denies targeting civilians during what it calls its "special military operation" in Ukraine and has said in the past that accusations of human rights abuses are a smear campaign.

The governor of Kharkiv region, Oleh Synhubov, told reporters on Friday at one of the burial sites in the city of Izium that some bodies exhumed there had been found with their hands tied behind their backs.

Moscow has not commented on the mass burial site in Izium, which was a Russian frontline stronghold before Ukraine's counter-offensive forced its forces to flee.

NO EARLY END TO WAR

Friday's interview took place in the president's office in the heavily-guarded government district, which is now like a citadel for Zelenskiy and his advisers. Sandbags were piled up in the windows of the building's labyrinthine, dimly-lit corridors.

An air raid siren - used to warn of the danger of incoming missiles - sounded in Kyiv shortly before the interview.

Zelenskiy, who visited Izium on Wednesday, repeated his appeal for Western countries and others to step up weapons supplies to Ukraine.

"We would want more help from Turkey, We would want more help from South Korea. More help from the Arab world. From Asia," he said.

Zelenskiy also cited "certain psychological barriers" in Germany to supplying military equipment because of its Nazi past but said such supplies were vital for Ukraine to defend itself against what he called Russian "fascism". He has often accused Berlin of dragging its feet over providing arms.

He lauded Ukraine's rapid counter-offensive but played down any suggestion that the war was entering some kind of end game. "It's early to talk about an end to this war," he said.

Zelenskiy said he would only support the idea of reopening Russian ammonia exports through Ukraine, an initiative proposed by the United Nations, if Moscow handed back Ukrainian prisoners of war to Kyiv.

Speaking in Uzbekistan on Friday, Russian President Vladimir Putin brushed off Ukraine's counter-offensive with a smile, but warned that Russia would respond more forcefully if its troops were put under further pressure.

Zelenskiy said he had been convinced that foreign weapons supplies to Ukraine would have fallen if Kyiv had not launched its counter-offensive and that the territorial gains would impress other countries.

"I think this is a very important step that influenced, or will influence, the decisions of certain other countries," he said.

Asked on the 205th day of the war if he ever got a chance to relax, Zelenskiy said: "I'd really want the Russians to relax".

(Editing by Gareth Jones)