Russia and China expressed alarm on Monday over the regional repercussions of two Israeli air raids on Syria, while Israel played down strikes which its officials said targeted Iranian missiles bound for Lebanese Hezbollah militants.
Oil prices spiked above $105 a barrel, their highest in nearly a month, on Monday morning as the air strikes on Friday and Sunday prompted fears of a wider spillover of Syria's two-year-old civil war that could affect Middle East oil exports.
Israel, whose prime minister visited China on Monday in a sign of business-as-usual, sought to persuade Syrian President Bashar al-Assad on Monday that the air strikes did not aim to weaken him and dismissed the prospects of an escalation.
"There are no winds of war," Yair Golan, the general commanding Israeli forces on the Syrian and Lebanese fronts, told reporters while out jogging with troops.
"Do you see tension? There is no tension. Do I look tense to you?" he said, according to the Maariv NRG news website.
The attacks hit targets manned by Assad's elite troops in the Barada River valley and Qasioun Mountain, residents, activists and opposition military sources said. They included a compound linked to Syria's chemical weapons programme, air defences and Republican Guards' facilities, the sources said.
The Syrian Observatory for Human Rights said at least 42 soldiers were killed and 100 more were missing, while other opposition sources put the death toll at 300 soldiers.
Russia said it was concerned the chances of foreign military intervention in Syria were growing, suggesting its worry stemmed in part from media reports about the alleged use of chemical weapons in the conflict that has killed 70,000 people.
Russian Foreign Ministry spokesman Alexander Lukashevich said the reported air strikes "caused particular alarm".
"The further escalation of armed confrontation sharply increases the risk of creating new areas of tension, in addition to Syria, in Lebanon, and the destabilisation of the so-far relatively calm atmosphere on the Lebanese-Israeli border."
Assad's government accused Israel of effectively helping al Qaeda Islamist "terrorists" and said the strikes "open the door to all possibilities". It said many civilians had died.
Israel has not confirmed the attack officially, but has reinforced anti-missile batteries in the north. Israeli officials said that, as after a similar attack in the same area in January, they were calculating Assad would not pick a fight with a well-armed neighbour while preoccupied with survival.
Syria would be no match for U.S. ally Israel in any direct military showdown. But Damascus, with its leverage over Lebanon's Hezbollah, could still consider proxy attacks through Lebanon.
Israeli officials said the raids were not connected with Syria's civil war but aimed at stopping Hezbollah, an ally of Iran, acquiring weapons to strike Israeli territory if Israel were to attack Iranian nuclear sites.
Iran denies Israeli and Western accusations that it is bent on acquiring atomic weapons - a long-running dispute that now threatens to intersect with the bloody strife in Syria.
Tehran, which has long backed Assad, whose Alawite minority has religious ties to Shi'ite Islam, denied Israel's attack was on arms. Shi'ite Hezbollah did not comment.
China, hosting Netanyahu, urged restraint and the respect of sovereignty, without mentioning Israel by name. Moscow and Beijing, allies of Assad, have blocked Western-backed measures against Assad at the United Nations Security Council.
A U.S. official said U.S. Secretary of State John Kerry was due to meet Russian President Vladimir Putin on Tuesday to see if he could persuade Moscow to support U.S. peace efforts.
Following the air strikes, the United Nations said Secretary-General Ban Ki-moon called on all sides "to act with a sense of responsibility to prevent an escalation of what is already a devastating and highly dangerous conflict".
The military in Turkey, one of Assad's most vocal critics and home to more than 400,000 refugees from the civil war that grew out of protests against his rule, launched a 10-day military exercise on Monday at a base near the border.
The violence in Syria has inflamed wider regional tensions between Shi'ite Muslim Iran and Sunni-ruled Arab states, some of them close allies of the West.
Senior Republican Senator John McCain said on Sunday that the Israeli air strikes could add pressure on Washington to intervene in Syria, although President Barack Obama has said he has no plans to send ground troops.
After Friday's raid, Obama defended Israel's right to block "terrorist organisations like Hezbollah" from acquiring weapons. A U.S. intelligence official said on Sunday Washington was not given any warning before the air strikes.
Additional reporting by Alexei Anishchuk in Moscow, Michael Martina in Beijing, Marwan Makdesi in Damascus and Jonathon Burch in Ankara; Writing by Philippa Fletcher; Editing by Peter Graff