Vladimir Putin hosted his "dear friend" Xi Jinping for dinner at the Kremlin on Monday, showing off his relationship with his most powerful ally just days after an international court called for the Russian president's arrest for war crimes in Ukraine.

Washington denounced Xi's visit, saying the timing indicated Beijing was providing Moscow with "diplomatic cover" to commit additional crimes.

It was the first trip abroad for Xi since he obtained an unprecedented third term earlier this month. The Chinese leader has been trying to portray Beijing as a potential peacemaker in Ukraine, as he deepens economic ties with his closest ally.

Putin and Xi greeted one another as "dear friend" when they met in the Kremlin, and Russian state news agencies later reported they held informal talks for nearly 4-1/2 hours, with more official talks scheduled for Tuesday.

In televised comments after they greeted each other, Putin told Xi he viewed China's proposals for a resolution of the Ukraine conflict with respect. He confessed to being "slightly envious" of China's "very effective system for developing the economy and strengthening the state".

Xi, for his part, praised Putin and predicted Russians would re-elect him next year.

"Under your strong leadership, Russia has made great strides in its prosperous development," he said.

Moscow has been publicly promoting plans for a visit by Xi for months. But the timing gave the Chinese leader's personal support new meaning, after the International Criminal Court issued an arrest warrant on Friday accusing Putin of war crimes for deporting children from Ukraine.

Moscow denies illegally deporting children, saying it has taken in orphans to protect them. It opened a criminal case against the court's prosecutor and judges. Beijing said the warrant reflected double standards.

The West says the warrant should make the Russian leader a pariah.

"That President Xi is travelling to Russia days after the International Criminal Court issued an arrest warrant for President Putin suggests that China feels no responsibility to hold the Kremlin accountable for the atrocities committed in Ukraine," U.S. Secretary of State Antony Blinken said.

"Instead of even condemning them it would rather provide diplomatic cover for Russia to continue to commit those grave crimes.”

White House spokesman John Kirby said Xi should use his influence to press Putin to withdraw troops from Ukraine, and Washington was concerned that Beijing might instead call for a ceasefire that would let Russian troops stay.

China has released a proposal to solve the Ukraine crisis, largely dismissed in the West as a ploy to buy Putin time to regroup his forces and solidify his grip on occupied land.

Russia and China "do not have the same network of friends and partners" around the world as the United States, and that's why they are tightening their relationship now, Kirby said.

"It's a bit of a marriage of convenience, I'd say, less than it is of affection," Kirby told reporters.

Washington has said in recent weeks it also fears China might arm Russia, which Beijing has denied.

KYIV CAUTIOUS

Kyiv, which says the war cannot end until Russia pulls out its troops, has been circumspect towards China, cautiously welcoming Beijing's peace proposal when it was unveiled last month even though Western allies were publicly skeptical.

Ukrainian President Volodymyr Zelenskiy has said that China arming Russia could lead to World War Three, but also that he believed Beijing was aware of this risk, implying he thought it was unlikely. He has called for Xi to speak to him.

Putin signed a "no limits" partnership with Xi last year shortly before the Kremlin leader ordered the invasion of Ukraine. Putin claims he aims to end a threat to Russia from its neighbor's moves towards the West; Kyiv and the West call it an unprovoked attack on an independent state.

Russia's assault is believed to have killed tens of thousands of Ukrainian civilians and soldiers on both sides. Moscow has destroyed Ukrainian cities, set millions of people to flight and claims to have annexed nearly a fifth of Ukraine.

The Kremlin said Putin would provide Xi with detailed "clarifications" of Russia's position, without elaborating.

Several European Union countries agreed in Brussels on Monday to jointly buy 1 million rounds of 155 mm artillery shells for Ukraine. Both sides fire thousands of rounds per day.

The United States announced its latest military aid package, worth $350 million, including more ammunition for HIMARS rocket launchers, howitzers and Bradley Infantry Fighting Vehicles, plus HARM missiles, anti-tank weapons and river boats.

Fierce fighting continued in the eastern Ukrainian town of Bakhmut, where Ukrainian forces have held out since last summer in the longest and bloodiest battle of the war.

Moscow, which has not scored a major victory since August, has launched a massive winter offensive involving hundreds of thousands of freshly called-up reservists and convicts recruited from jails.

Fighting that both sides describe as a meat grinder has scattered the battlefield with bodies, but the front line has barely moved for more than four months.

Ukraine, which recaptured swathes of territory in the second half of 2022, has kept mainly to defense since November, aiming to deplete Russia's attacking forces before launching a planned counteroffensive of its own.