GENEVA/MOSCOW/BUDAPEST - Days before the fourth anniversary of the start of the Ukraine-Russia conflict, the two-day talks among Ukraine, the United States and Russia, marking the third round of trilateral talks this year, concluded on Wednesday with no breakthrough on key issues.

The first-day talks lasted six hours in both bilateral and trilateral formats, while the second-day talks lasted two hours, Russian media reported.

Ukrainian President Volodymyr Zelensky said that no agreement on key issues was reached, according to media reports.

"We can see that some groundwork has been done, but for now, positions differ because the negotiations were not easy," Zelensky told reporters in a WhatsApp chat on Wednesday.

Ukraine's chief negotiator Rustem Umerov, also Ukraine's National Security and Defense Council Secretary, said that the work was intense and subjective.

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"There is progress, but no details at this stage," He wrote in a Facebook post.

Zelensky also told Ukrainian media that monitoring of a ceasefire with US participation, as well as sensitive political issues such as Donbas and the Zaporizhzhia Nuclear Power Plant, were all discussed during the talks.

Describing the talks as difficult but business-like, Russia's presidential aide Vladimir Medinsky noted that a new round of negotiations will be held in the near future.

No documents were signed during the talks, RIA Novosti reported Wednesday.

The Russian Foreign Ministry announced on Wednesday that the Russian delegation had clear instructions to act within the framework of understanding from the meeting between Russian President Vladimir Putin and US President Donald Trump that was held in the US city of Anchorage, Alaska in August last year.

Umerov said on Facebook that the next stage is to reach the required level of consensus to make well-known decisions for the presidents' consideration. He emphasized that the ultimate goal remains unchanged: a just and sustainable peace.

Two previous rounds of trilateral talks, held in Abu Dhabi on Jan 23-24 and Feb 4-5, did not resolve key territorial issues.

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Fighting even continued between Russia and Ukraine before Tuesday's talks.

Safet Music, a security expert in Bosnia and Herzegovina, told Xinhua that diplomacy serves more as a tool of conflict management than resolution, as the situation has entered a prolonged conflict of attrition in which neither Moscow nor Kyiv can achieve a decisive breakthrough without enormous costs.

"The Ukraine-Russia conflict is exhausting all parties concerned and draining both Russian and European human and material resources, with no end in sight," Nasser Saidi, founder and president of Nasser Saidi & Associates, shared his view with Xinhua.

Russia warning on Japan’s possible participation

Also on Wednesday, Russia warned that Japan's possible participation in a North Atlantic Treaty Organization (NATO) arms procurement mechanism for Ukraine would further strain bilateral relations and that military equipment funded by Japan would become legitimate targets for Russian forces.

Maria Zakharova, spokeswoman for the Russian Foreign Ministry, said at a regular briefing that Moscow had received reports about Japan's intention to join a NATO mechanism for purchasing military equipment for Ukraine.

"These steps will further complicate Russia-Japan relations, which, through Tokyo's actions, have already been in a state of deep stagnation," she said.

Zakharova added that military equipment supplied to Ukraine with Japanese funds would become legitimate targets for Russian forces.

In April last year, former Japanese Prime Minister Shigeru Ishiba said after meeting with NATO Secretary General Mark Rutte that Japan saw great potential in developing defense industry cooperation with the alliance.

Earlier this month, Japan's public broadcaster NHK reported that Japan would soon announce its participation in a NATO assistance program aimed at purchasing weapons and equipment from the United States and supplying them to Ukraine.

Hungary suspends diesel fuel deliveries to Ukraine

Meanwhile, Hungary has suspended diesel fuel deliveries to Ukraine with immediate effect and will not resume shipments until crude oil transit via the Druzhba pipeline is restored, Hungarian Minister of Foreign Affairs and Trade Peter Szijjarto said here on Wednesday.

The suspension will remain in place until Ukraine restarts crude oil deliveries to Hungary through the pipeline, Szijjarto told a press conference following a government meeting.

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According to the minister, crude oil transit was halted on Jan 27.

The Druzhba pipeline, which carries Russian oil through Ukraine to Central Europe, has faced repeated disruptions since last year due to damage to energy infrastructure amid the ongoing Russia-Ukraine conflict.