U.S. Secretary of State Antony Blinken on Monday warned the international community not to be misled by Russia and China over the Ukraine war, as Chinese President Xi Jinping began a high-profile state visit in Moscow.

Blinken said that any plan for ending the war must uphold Ukraine's sovereignty and territorial integrity in accordance with the U.N. Charter. Efforts lacking such provisions, the top U.S. diplomat said, are merely seeking to promote an "unjust outcome."

U.S. Secretary of State Antony Blinken. (Kyodo)

"The world should not be fooled by any tactical move by Russia, supported by China or any other country, to freeze the war on its own terms," he told reporters, shortly after Russian President Vladimir Putin welcomed Xi warmly and the two shared a mutual greeting as "dear friend."

Blinken also highlighted that Xi's three-day visit to the Russian capital, taking place just days after the issuing of an arrest warrant for Putin by the International Criminal Court, signals that Beijing "feels no responsibility to hold the Kremlin accountable for the atrocities committed in Ukraine."

The comments were made as the administration of President Joe Biden has raised alarms over the possibility of Xi presenting himself as a peace broker and calling for a cease-fire between Russia and Ukraine.

Blinken said such a proposal made by China last month would not be a "durable solution." He said it would only enable Putin to refit the Russian military and "then restart the war at a time more advantageous" to his country.

On Monday, the U.S. government announced the authorization of further military aid to Ukraine to help it avoid running out of ammunition and better defend itself against Russia.

The package, worth up to $350 million, will be the 34th drawdown of U.S. arms and equipment for Ukraine since August 2021. It includes more ammunition for multiple-launch High Mobility Artillery Rocket Systems, or HIMARS, as well as anti-radiation missiles and heavy fuel tankers.

Later in the day, White House national security spokesman John Kirby spoke in a similar vein, urging Xi to press Putin to bring an immediate end to the bombing of Ukrainian cities and the carrying out of atrocities by Russian forces in the country.

Kirby said he believes Putin sees Xi as a "lifeline of sorts for a war that he's conducting that has clearly not gone in anywhere near the direction he wanted it to go."

"So it's a bit of a marriage of convenience," he said. "We will see where this goes after this meeting."

The spokesman reiterated that keeping lines of communication open between Washington and Beijing is particularly important at a time when tensions are high.

While regretting that military-to-military channels remain closed, he disclosed that the two countries are having discussions about a potential visit to China by Treasury Secretary Janet Yellen and Commerce Secretary Gina Raimondo to talk about economic issues.

In early February, Blinken abruptly postponed his planned visit to Beijing after Washington detected what it called a Chinese spy balloon traveling over sensitive areas of the continental United States.

The trip, which was intended to be a follow-up on Biden and Xi's face-to-face talks in November, would have been the first visit to China by a ministerial-level official from Washington since the current U.S. administration's inception in 2021.

Kirby said the U.S. government is still interested in working toward having Blinken in Beijing, and Biden is also prepared to have another conversation with Xi "at the most appropriate time."

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