Foreign Minister Yair Lapid on Thursday condemned Russia's full-scale invasion of Ukraine, which began hours earlier, calling it a "severe violation of international order".
Israel has remained neutral on the conflict between Russia and Ukraine as tensions between the two countries intensified in recent days. On Wednesday, the Foreign Ministry issued a statement, expressing support for Ukraine's sovereignty but stopped short of condemning Russia.
"The Russian attack all across Ukraine is a serious violation and Israel condemns it. Israel has known conflicts and war is not the way to resolve them. One can still stop and settle the disputes," Lapid said in a statement.
The foreign minister added that Israel "has good relations with both Russia and Ukraine" and called on Israeli citizens still in Ukraine to leave the country.
Russian forces invaded Ukraine by land, air and sea early Thursday morning, confirming the worst fears of the West with the biggest attack by one state against another in Europe since World War Two.
Russian missiles rained down on Ukrainian cities, while Ukraine reported columns of troops pouring across its borders into the eastern Chernihiv, Kharkiv and Luhansk regions, and landing by sea at the port cities of Odessa and Mariupol in the south.
President Yitzhak Herzog, who is currently on a state visit to Greece, also addressed the events in Ukraine, saying he fears "a humanitarian tragedy and harm that could be done to innocent civilians".
This is a very complex historical moment," he said, adding that he urges Israelis in Ukraine to "return through land crossings" since all flights in and out of the country have been suspended.
Ukraine, a democratic country of 44 million people with more than 1,000 years of history, is Europe's biggest country by area after Russia itself. It voted overwhelmingly for independence after the fall of the Soviet Union, and aims to join NATO and the European Union, aspirations that infuriate Moscow.
Putin, who denied for months that he was planning an invasion, has called Ukraine an artificial creation carved from Russia by its enemies, a characterization Ukrainians call shocking and false.
Reuters contributed to this report