The United States is on high alert, bracing for potential attacks by Iran on Israeli or American assets in the region, following Israel's recent strike on the Iranian embassy in Syria's Damascus.
"We're definitely at a high state of vigilance," the official said in confirming a CNN report that said an attack could come in the next week.
The strike on Iran's embassy in Damascus, suspected to be conducted by Israeli warplanes, resulted in the death of an Iranian military commander, escalating tensions between Israel and its regional adversaries.
The Islamic Revolutionary Guard Corps confirmed the deaths of seven Iranian military advisers, including Mohammad Reza Zahedi, a senior commander in its Quds Force.
In response to the strike, thousands gathered for the funeral of the Iranian Revolutionary Guards killed in Syria, chanting anti-Israel and anti-US slogans. Iranian officials warned of consequences for Israel, with General Hossein Salami stating that Israel "cannot escape the consequences" of its actions.
The strike coincided with Quds Day, a day of pro-Palestinian rallies supported by Iran and its allies. Similar demonstrations took place in Syria, Iraq, Yemen, and Bahrain, with Hezbollah's leader delivering a speech in Lebanon.
US President Joe Biden discussed the threat from Iran in a phone call on Thursday with Israeli Prime Minister Benjamin Netanyahu.
"Our teams have been in regular and continuous contact since then. The United States fully supports the defense of Israel against threats from Iran," a senior Biden administration official said.
Israel responded by strengthening its defenses and halting leave for combat units.
'Mourners held Iranian, Palestinian flags and Hezbollah flags, chanting "Death to Israel!" and "Death to America!"'
Ziyad al-Nakhalah, leader of Palestinian militant group Islamic Jihad which fights alongside Hamas in Gaza, attended the funeral, Iran's Fars news agency reported. President Ebrahim Raisi and his predecessor Hassan Rouhani were also present.
Guards chief Salami said Tehran was determined to make Israel pay for the raid. "The Zionist regime cannot escape the consequences of the harm it does," he said, adding: "It is exposed and knows very well what is going to happen."
Iran's supreme leader Ayatollah Ali Khamenei has said Israel "will be punished" for the killings.
Hezbollah says yet to use 'main' weapons against Israel
The leader of Lebanon's Hezbollah movement warned Friday his group had not yet used its main weapons in nearly six months of cross-border exchanges with Israel since the Gaza war began.
"We have not employed our main weapons yet, nor have we used our main forces," Hassan Nasrallah said in a televised speech marking Quds (Jerusalem) Day -- an annual day of pro-Palestinian rallies held by Iran and its allies.
(Agencies)
Bob Blackman MP speaks during the event