The United States is on high alert and preparing for a “significant” Iranian attack that could target Israeli or U.S. assets in the region within the next week, an official told CNN on Friday.Anticipated attacks will respond Israel attacks Iranian embassy in Syria Killed a senior commander.

The official told CNN that senior U.S. officials and Israeli counterparts believe an Iranian attack is “inevitable.” The official added that as of Friday, the two governments did not know when or how Iran planned to strike back.

An airstrike on an Iranian diplomatic compound in the Syrian capital killed Gen. Mohammad Reza Zahedi, the top commander of Iran’s Quds Force. It was the most high-profile killing since Quds Force commander Maj. Gen. Qasem Soleimani was killed in a U.S. drone strike in 2020.

The worst-case scenario facing the United States would be a direct Iranian attack on Israel. This would cause Israel’s war with Hamas to expand into a broader regional conflict and escalate the already volatile situation in the Middle East.

Israel expects a response from Iran after April 5, the last Friday of Ramadan. Iran designated this day as Jerusalem Day to show its support for the Palestinians.

In response to possible retaliatory attacks by Iran, Israeli authorities step up GPS jamming effortsdisrupting navigation services across the country to defend against possible missiles and drones.