U.S. embassy locks down diplomats in Israel as officials fear Iranian attack with '100 drones and dozens of missiles' and White House warns threat is 'real, credible, and viable'

The U.S. embassy in Jerusalem has imposed travel restrictions on diplomats living in Israel as officials fear an Iranian attack could be coming using 100 drones and dozens of missiles. 

An Iranian attack would be in retaliation for an April 1 strike on a building adjacent to the Iranian embassy in Damascus, Syria, which Israel has not claimed responsibility for. 

The White House on Friday wouldn't go as far as to say that an attack was 'imminent,' instead calling the threat 'viable.' 

'We still deem the potential threat by Iran here to be real, to be viable, certainly credible and we're watching it as closely as we can,'  White House National Security Council spokesman John Kirby told reporters Friday on a Zoom call. 

Kirby added that the U.S. was in 'constant communication with our Israeli counterparts about making sure that they can defend themselves against those kind of attacks.' 

The NSC spokesperson gave no details on the potential timing of such an attack. 

'I really don't want to get into armchair quarterbacking this thing in a public way in terms of the conversations we're having or what we're seeing in the intelligence picture,' Kirby said.  

On Thursday, the U.S. embassy in Jerusalem did not explicitly mention Iran but issued a warning to government workers. 

'Out of an abundance of caution, U.S. government employees and their family members are restricted from personal travel outside the greater Tel Aviv, … Jerusalem, and Be’er Sheva areas until further notice,' the security alert read. 

The April 1 attack in Damascus killed two senior members of the Islamic Revolutionary Guard Corps and five other officers, Iran said. 

Israel has yet to claim responsibility publicly.  

The Washington Post reported Thursday that senior Pentagon officials were frustrated that the U.S. did not get a heads up from Israel before conducting an airstrike on the Iranian site.