US believes Iran could attack Israel, with potential to escalate war in the region

The United States believes Iran may retaliate against Israel in coming days, according to two sources familiar with intelligence on the matter.

The intelligence that Iran could use drones and missiles to attack "regional assets" by Israel has been shared with U.S. lawmakers.

U.S. officials believe the attacks would be done in retaliation for Israel's airstrike in Damascus, Syria, last week, which killed a top commander in the Iranian Revolutionary Guard Corps along with six other personnel. If Iran's retaliatory happens, officials believe the attacks have the potential to widen the scope of the war in Gaza.

"They're threatening to launch a significant attack on Israel," Biden said at a news conference Wednesday.

"As I told Prime Minister [Benjamin] Netanyahu, our commitment to Israel's security against these threats from Iran and its proxies is ironclad. Let me say it again, ironclad. We're going to do all we can to protect Israel's security," he added.

Last week, Iran's Foreign Minister Hossein Amirabdollahian said Israel "will be punished and that America is responsible for the regime's attack on the Iranian embassy and must be held accountable."

"The response will be crushing," he added.

Israel's foreign minister, Israel Katz, posted a warning Wednesday to Iran on the social media site X.

"If Iran attacks from its territory, Israel will respond and attack in Iran," Katz wrote.

Israel's Defense Minister Yoav Gallant made similar remarks Wednesday.

"We will know to respond very quickly in a necessary offensive in the territory of whoever attacks Israel, no matter where -- anywhere in the Middle East," Gallant said while visiting an Iron Dome battery in Israel's north.

According to one U.S. official, it's believed that Iran could choose to retaliate in a proportional response targeting an Israeli diplomatic facility like the Iranian diplomatic location that was struck on Monday in Syria . Or, the official said, it's possible that Iran could strike directly at Israel.

A second person familiar with the intelligence confirmed that officials believed Israel's "regional assets" were at significant risk.

Threats to U.S. assets is less clear. Officials have long been concerned that Iranian-backed militias might resume targeting U.S. forces in Iraq and Syria.

Those attacks stopped Feb. 4 following U.S. airstrikes in retaliation for the death of three service members.

But while U.S. officials say they do not see any specific threats to troops in the region, the concern remains that an Iranian attack could further destabilize the region.

ABC News' William Gretsky contributed to this report.