Israel said it would not allow advanced weapons to fall into the hands of Hezbollah, after reports it had attacked a Syrian air base holding missiles for the militant group.
Israel declined to comment on media reports that its planes had hit the base near the port of Latakia.
However, Home Front Defence Minister Gilad Erdan told Israeli radio: "We have said many times that we will not allow the transfer of advanced weapons to Hezbollah. We are sticking to this policy and I say so without denying or confirming this report."
A quite extraordinary situation has developed in the Middle East, where Israel can carry out airstrikes on what used to be a great power, Syria, and it can do so with impunity.
Israel has made no comment on the air strike, which reportedly targeted a missile delivery, but then it never does. Six times now, by my count so far this year, Israel has carried out air strikes inside Syria.
They're all on similar targets, sophisticated weapons such as surface-to-air missiles made in Russia, that Israel thinks are in the process of being delivered to the Assad regime's great ally, the Lebanon-based militia group Hizbollah.
There has also been no comment from the Assad regime on this air strike, certainly no kind of military response. The Assad regime of course has its hands full fighting the civil war.
Israeli fighters which struck a Syrian airbase near the port of Latakia were targeting missiles that were thought to be on their way to Lebanese militia group Hezbollah, said Reuters citing an an unidentified US administration official who spoke to CNN.
The airstrike on Thursday was the latest of several carried out by Israel this year, which has said it will act to defend its territory if needed. Israel does not comment on its military operations.
The attack involved two to four aircraft, said USA Today citing a security official speaking to AP.
Israeli warplanes mounted a new attack on a Syrian military base on Thursday, according to a US official cited by the Associated Press.
The strike hit the Syrian port city of Latakia and the target was Russian-made SA-125 missiles, according to the anonymous security official.