Flight times are expected to be longer as airlines avoid Iranian airspace and air fares are also expected to increase.

Israel’s El Al Airlines was reported to have cancelled 15 flights scheduled over Saturday and Sunday, and Austrian Airlines was also reported to have cancelled all its flights to Iran until April 18.

United Airlines said it had cancelled its service to Tel Aviv.

“We have cancelled Saturday’s planned flight from Newark to Tel Aviv and its associated return flight due to restrictions on Israeli airspace,” a spokesman said.

“We are closely monitoring the situation and will make decisions on upcoming flights with a focus on the safety of our customers and crews.”

A Lufthansa spokesman, on behalf of the firm including its subsidiary Austrian Airlines, said: “We have temporarily stopped overflying Iranian airspace until April 18. Security is our number-one priority.”

Qantas had already paused its non-stop flights from Perth to London in a bid to avoid Iranian airspace due to fears of the impending attack on Israel.

The route has now been changed and has a stop in Singapore in place due to the situation.

A Qantas spokesman said: “We’re temporarily adjusting the flight paths for our flights between Perth and London due to the situation in parts of the Middle East. We’ll reach out to customers directly if there’s any change to their booking.”

The UK along with the US were among the countries issuing a travel warning to those looking to travel to the region, along with France, Canada and Australia.
Dutch airline KLM also said it would no longer fly over Iran or Israel, according to Dutch press agency ANP on Saturday.

KLM, the Dutch arm of Air France-KLM, said the move was a precaution, but it indicated it would continue flying to Tel Aviv.