Iran warned it would defend itself after Israeli air strikes killed at least four soldiers and further stoked fears of a full-scale war in the Middle East.

Israel sent a message to Iran on Friday ahead of its retaliatory airstrikes warning the Iranians not to respond, three sources with knowledge of the issue told U.S. news portal Axios.

The U.S. and Britain called for "de-escalation" after Israel on Saturday hit military targets across Iran in deadly retaliatory strikes as Muslim countries blamed Israel for exacerbating the conflict.

Israel’s opposition leader Yair Lapid praised the work of the military but said Israel should have struck harder.

“The decision not to attack strategic and economic targets in Iran was wrong. We could and should have exacted a much heavier price from Iran,” Lapid wrote in a post on X.

Syrian state news agency SANA said Israel conducted an air attack on Saturday from the occupied Golan Heights and Lebanon, targeting military positions in Syria.

Iran said it was obliged to defend itself, after Israeli retaliatory strikes hit military targets and killed two soldiers in the Islamic republic on Saturday.

The United States urged Iran on Saturday to stop attacking Israel to break the cycle of violence after Israel launched strikes against the Islamic republic in retaliation for a missile barrage.

Saudi Arabia condemned Israeli strikes on military targets in Iran on Saturday, warning against any further expansion of the conflict in the Middle East.

The Iranian army said two soldiers were killed in Israeli air strikes on military installations in the Islamic republic on Saturday, according to a statement carried by state television.

Israel attacked Iran with a series of pre-dawn airstrikes Saturday in what it said was a response to the barrage of ballistic missiles the Islamic Republic fired upon Israel earlier in the month.

The Israeli military said its aircraft targeted facilities that Iran used to make missiles fired at Israel as well as surface-to-air missile sites. There was no immediate indication that oil or missile sites were hit — strikes that would have marked a much more serious escalation — and Israel offered no immediate damage assessment.