Ukraine's Volodymyr Zelenskyy said on Tuesday that if U.S. President Joe Biden missed a peace summit organized by Kyiv in Switzerland next month, Russian President Vladimir Putin would applaud his absence.

Ukraine hopes to host as many countries as possible in an attempt to unite opinions on how to halt the war and pile pressure on Russia, which has seized almost a fifth of Ukraine's territory. Washington has signaled support but has not said whether Biden will attend.

"I know that the U.S. supports the summit, but we don't know at what level," the Ukrainian president said in Brussels on Tuesday at a joint press conference with Belgian Prime Minister Alexander De Croo.

KYIV'S FORCES ARE UP AGAINST A CONCERTED RUSSIAN PUSH IN EASTERN UKRAINE, A MILITARY OFFICIAL SAYS

"(The) peace summit needs President Biden and so do the other leaders who look at the reaction of the United States. Putin will only applaud his absence, personally applaud it - and standing, at that."

Zelenskyy on Sunday urged both Biden and Chinese President Xi Jinping, Putin's close ally and a leading beneficiary of his rift with the West, to attend the summit.

Russia, which launched a full-scale invasion of Ukraine in February 2022, has said it sees no point in the conference.