"These companies, starting from 8:00 pm (1630 GMT) Tehran time on Wednesday, April 1, should expect the destruction of their relevant units in exchange for every assassination in Iran," the Guards said in a statement listing the names of 18 companies it alleged were complicit in the killing of officials.

"We advise the employees of these institutions to immediately leave their workplaces to preserve their lives," it added.

The threat comes as President Donald Trump says he is conducting diplomacy aimed at putting an end to the conflict, while also threatening to amplify the US-Israeli campaign against the Islamic republic.

The Guards' statement said the U.S. government and tech giants had "ignored our repeated warnings regarding the necessity" of halting operations targeting top Iranian officials, alleging that the tech firms are the "main element in designing and tracking assassination targets".

As a result, these 18 companies -- who also included Intel, Microsoft and Oracle, as well as electric car company Tesla, analytics firm Palantir, and chip giant Nvidia -- risk retaliation, the statement said.

"Companies that actively participate in terrorist designs will face reciprocal action for every targeted assassination," the statement said.

Microsoft headquarters in Paris. Photo by AFP

The warning did not specify where the action would take place, but it added:

"Residents around these terrorist companies in all countries of the region are also advised to leave their locations within a one-kilometre radius and move to a safe place."

In early March, Amazon reported that two of its data centres in the United Arab Emirates were "directly struck" by drones and one in Bahrain damaged by a nearby attack.

Supreme leader Ali Khamenei and Revolutionary Guards commander-in-chief Mohammad Pakpour were killed on the first day of the war on February 28, with the U.S. and Israel seeking to kill an entire echelon of the Iranian leadership.

The Islamic republic's powerful security chief, Ali Larijani, has also been killed, as have many other prominent figures.

Israel and the United States say they have dealt a major blow to Iran by killing top officials, but some analysts say the Islamic republic is showing resilience and capacity to recover from the setbacks.

Also on Tuesday, Iran's army said that in response to attacks on Iranian infrastructure its drones had targeted key "communications, telecommunications and industrial centres" in Israel including centres of industrial giants Siemens close to the main international airport and AT&T in the city of Haifa.

There was no immediate confirmation from Israel that these targets had been hit.