China made the comments in a 12-point paper on the "political settlement" of the crisis, timed to coincide with the one-year anniversary of Russia's invasion of Ukraine.

"All parties should support Russia and Ukraine in working in the same direction and resuming direct dialogue as quickly as possible," said the paper, released on the foreign ministry's website.

Russian President Vladimir Putin has threatened to use nuclear weapons in the conflict.

China made clear its opposition to not only the use of nuclear weapons, but the threat of deploying them.

"Nuclear weapons must not be used and nuclear wars must not be fought. The threat or use of nuclear weapons should be opposed," the statement said.

China also highlighted the need to protect civilians.

"Parties to the conflict should strictly abide by international humanitarian law, avoid attacking civilians or civilian facilities," it said.

China has sought to position itself as a neutral party in the conflict while maintaining close ties with strategic ally Russia.

Top Chinese diplomat Wang Yi met on Wednesday with Russia's foreign minister Sergei Lavrov and President Vladimir Putin in Moscow.

Following Wang's visit, Moscow said Beijing had presented its views on approaches to a "political settlement" of the conflict.

Ukrainian President Volodymyr Zelensky said Thursday he had not seen any Chinese peace plan and wanted to meet with Beijing over their proposal before assessing it.

"I think it is a very good fact in general that China started talking about Ukraine and sent some signals," Zelensky said.

"We'll draw some conclusions after we see the specifics of what they offer... We would like to have a meeting with China."

Since Russian tanks rolled over the border into Ukraine, China has offered Putin diplomatic and financial support, but refrained from overt military involvement or sending caches of lethal arms.

Chinese state-controlled firms have sold non-lethal drones and other equipment to both Russia and Ukraine, but Moscow has been forced to turn to Iran for much-needed supplies such as unmanned aerial vehicles.

The United States has said North Korea has also provided rockets and artillery shells.

Washington believes that might be about to change, with both the United States and NATO voicing concerns that China could be planning to supply Russia with weapons to prop up its war effort. Beijing has denied the claims.