China on Monday denied accusations by Ukrainian President Volodymyr Zelensky that it was trying to prevent other nations from attending a planned peace summit on the war in Ukraine.

Speaking Sunday at a security forum in Singapore, Zelensky accused Beijing of "working hard today to prevent countries from coming to the peace summit" due to be hosted by Switzerland this month.

Ukraine hopes the gathering will help it win broad international backing for its vision of the terms needed to end Russia's invasion.

But China criticised the conference last week, saying it would be "difficult" for it to attend if ally Russia did not participate.

Beijing's foreign ministry said Monday that "China's position is open and transparent, and there is absolutely no instance of us putting pressure on other countries".

"On peace talks, China's position is fair and just. It does not target any third country, and of course is not aimed at Switzerland's hosting of this summit for peace," spokeswoman Mao Ning said at a regular press briefing.

China "believes that all efforts conducive to the peaceful resolution of the crisis should be supported", she added.

Beijing insists it is a neutral party on the war in Ukraine, but has also faced sharp criticism from the West over its strategic partnership with Russia.

The United States has charged that China, while not directly sending weapons to Russia, has supported Moscow's largest defence industry expansion since Soviet times.

Russian President Vladimir Putin was in China last month, where he sought greater Chinese backing for his war effort and signed a joint statement with China's leader Xi Jinping on deepening their countries' strategic partnership.

- Peace summit -

On Sunday, Zelensky said more than 100 countries and organisations had signed up to the peace conference in Switzerland so far.

After Singapore, the Ukrainian leader flew to Manila for a meeting with Philippine President Ferdinand Marcos on Monday as he continued to push for the peace summit.

Zelensky told Marcos that the Philippines' agreement to participate in the conference would send a "very strong signal", according to a transcript of their remarks released by Manila.

During their meeting at the presidential palace, Zelensky also asked Marcos to send Filipino mental health workers to help Ukrainian troops.

"That is something that I think we are able to offer," Marcos said.

Underscoring their warm ties, Zelensky said Ukraine would open an embassy in Manila this year.