Gas deal

In an economic blow dealt to Europe under the shadow of conflict, Russian energy giant Gazprom said on Wednesday that it has stopped the gas supply for transit through Ukraine due to the expiration of key agreements and the lack of renewal by the Ukrainian side, according to Xinhua News Agency.

However, the European Commission played down the impact of the halt, saying the stop had been expected and that the bloc was prepared for it.

While the EU can probably continue to prop up Ukraine's ravaged economy, it is almost certainly unlikely to be able to provide the military backing that the country's armed forces would require to prevail.

However, economic aid from the West brings hope to Kyiv in maintaining its fight against Russia. The Biden administration recently transferred $20 billion to Ukraine, providing an urgently needed economic lifeline in the form of a loan that will be repaid using interest earned from Russia's frozen central bank assets.

Zelensky said Kyiv needs the EU and the US to stay united and that "only together" can the US and Europe "stop Putin and save Ukraine". He said that the only effective security guarantee remains NATO membership.

"I don't think Ukraine will join NATO as desired, judging from the current situation, but NATO and the US will possibly provide Ukraine with a certain level of security guarantee," said Wang Yong, a professor at the School of International Studies and director of the Center for American Studies at Peking University.

Andrey Sidorov, head of the world politics department at Moscow State University, agreed. He said Trump was not particularly enthusiastic about meeting Zelensky, although his advisers insisted that it was very necessary.

Sidorov said Moscow and Kyiv still have major differences of opinion.

"It will be challenging for Ukraine to accept the loss of territories, while sanctions from Russia are unlikely to be lifted even if peace is reached."

Liu Hongjie in Beijing and agencies contributed to this story.