>> UPDATE: Russia: Israeli strike in Syria only 'worsened stability'

Russian President Vladimir Putin and Prime Minister Benjamin Netanyahu spoke on Wednesday, and the Russian leader urged Israel not to take action in Syria and to threaten its security. Israeli officials confirmed the call took place and said that Netanyahu told Putin that Israel will not permit Iran to set up a military presence in Syria.

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Open gallery view Prime Minister Benjamin Netanyahu speaking at a Holocaust memorial event in Jerusalem on April 11, 2018. Credit: Emil Salman

The news of the telephone call between Netanyahu and Putin appeared as Netanyahu took the stage in Israel's main Holocaust memorial event and issued a threat to Iran not to "test Israel's resolve." The Russians announced the call in statement on the website of the Kremlin, which specified that Putin insisted it is "important" to maintain Syria's sovereignty.

Israel is on high alert for any Iranian retaliation after Tehran's direct threat Tuesday, as well as any possible U.S. strike against Syria's Assad regime in retaliation to the chemical attack at Douma.

Netanyahu lashed out at Iran during his Holocaust memorial speech, saying it was still intent on destroying Israel. Netanyahu also ripped into the landmark nuclear accord reached between Teheran and world powers and said: "I have a message for the leaders of Iran: Don't test Israel's resolve."

Netanyahu also took the opportunity to condemn the Syrian regime and the recent chemical attack in Syria, saying that "murderous evil that is not stood up against spreads rapidly."

>> This is not a drill: Syria showdown could spark Israeli-Iranian and U.S.-Russian clashes ■ Revenge by Iran could push Israel to terminate its Syrian presence

President Donald Trump appears to be closer to taking action in Syria after Saturday's deadly chemical attack, for which he vowed "animal Assad" would "pay a heavy price."

Trump tweeted early Wednesday morning, "Russia vows to shoot down any and all missiles fired at Syria. Get ready Russia, because they will be coming, nice and new and 'smart!' You shouldn’t be partners with a Gas Killing Animal who kills his people and enjoys it!"

>> Israel on high alert, prepares for possible Iranian retaliation after strike on Syrian base ■ Revealed: The Iranian compound targeted by the 'Israeli strike' in Syria

Trump followed that tweet with an assessment of U.S.-Russia relations, writing, "Our relationship with Russia is worse now than it has ever been, and that includes the Cold War. There is no reason for this. Russia needs us to help with their economy, something that would be very easy to do, and we need all nations to work together. Stop the arms race?"

The Kremlin took a jab at Trump in response, saying it did not engage in "Twitter diplomacy". Kremlin spokesman Dmitry Peskov was quoted as saying that care should be taken not to aggravate the situation in Syria.

"We do not participate in Twitter diplomacy," Peskov was quoted as saying by Interfax. "We support serious approaches. We continue to believe that it is important not to take steps that could harm an already fragile situation."

A Russian Foreign Ministry spokesperson responded to Trump's tweet, saying that "smart missiles should fly toward terrorists, not a legal government," adding that it could be a U.S. attempt to destroy evidence of the alleged chemical attack on the ground.

As Trump ramped up his threats, the Syrian military has repositioned some air assets to avoid the fallout from potential missile strikes, U.S. officials told Reuters on Wednesday.

The officials declined further comment and it was not clear whether the Syrian moves would impact U.S. military planning for potential action against Syria over a suspected poison gas attack.