Ukraine war live updates: Russia expresses 'extreme concern' and calls for restraint in Middle East, but refuses to condemn Iran

This is CNBC's live blog tracking developments on the war in Ukraine. See below for the latest updates. 

Russia's Foreign Ministry on Sunday expressed "extreme concern over another dangerous escalation" in the Middle East following Iran's missile and drone strike on Israel.

"We express our extreme concern at yet another dangerous escalation in the region. We have repeatedly warned that the numerous unresolved crises in the Middle East, primarily in the area of the Palestinian-Israeli conflict, which are often fueled by irresponsible provocative actions, will exacerbate tensions," the foreign ministry said on Telegram.

"We call on all parties involved in the conflict to exercise restraint. We expect the regional states to resolve the existing problems through political and diplomatic means. We believe it is important for the constructively-minded international players to contribute to this effort," it added.

Israel has vowed to retaliate for the Iranian strike, which itself was carried out to avenge an alleged Israeli airstrike that killed several top Iranian commanders in Damascus earlier in April.

Russia did not condemn Iran's attack, repeating Iran's assertion that the attack was "undertaken as part of the right to self-defence."

Ukraine's military chief said Russian forces are aiming to capture the town of Chasiv Yar in Donetsk by May 9, the date on which Russia commemorates Soviet victory in World War II.

Chasiv Yar lies west of Bakhmut, a town reduced to rubble but finally captured by Russian forces last May after months of fighting. Capturing the town would give Russia another strategic gain in Donetsk in eastern Ukraine, a war hot spot, and could allow it to advance on industrial hub Kramatorsk.

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