The United States expects an attack by Iran against Israel but one that would not be big enough to draw Washington into war, a US official said late on Thursday.

The White House said earlier Washington did not want conflict to spread in the Middle East and the US had told Iran it was not involved in an air strike against a top Iranian military commander in Damascus.

The White House added it warned Iran to not use that attack as a pretext to escalate further in the region.

Suspected Israeli warplanes bombed Iran’s embassy in Damascus on Monday in a strike for which Iran has vowed revenge and in which a top Iranian general and six other Iranian military officers were killed, ratcheting up tension in a region already strained by the Gaza war.

Iranian sources told Reuters Tehran has signalled to Washington that it will respond to Israel’s attack on its Syrian embassy in a way that aims to avoid major escalation and it will not act hastily, as Tehran presses demands including a Gaza truce.

The United States has been on high alert about possible retaliatory strikes from Iran and U.S. envoys have been working to lower tensions.

The US has restricted its employees in Israel and their family members from personal travel outside the greater Tel Aviv, Jerusalem and Be’er Sheva areas

“Out of an abundance of caution, U.S. government employees and their family members are restricted from personal travel outside the greater Tel Aviv (including Herzliya, Netanya, and Even Yehuda), Jerusalem, and Be’er Sheva areas until further notice,” the U.S. embassy said in a security alert on its website on Thursday. “U.S. government personnel are authorized to transit between these three areas for personal travel.”