United and Delta have suspended Israel service due to ramped-up tensions in the region.
Delta has suspended service through the end of August, while United has not set a resumption date.
"We continue to closely monitor the situation and will make decisions on resuming service with a focus on the safety of our customers and crews," United said.
United had been flying twice-daily to Tel Aviv from Newark, while Delta was offering a daily New York-Tel Aviv flight.
Tensions between Israel and Iran and Hezbollah have escalated dramatically in recent days following a July 28 Hezbollah rocket attack of the Israel-controlled Golan Heights, near Lebanon and Syria, which killed 12 people.
Israel responded to the attack with a targeted Beirut bombing that killed the terrorist group's senior military commander, Fuad Shukr. Israel is also believed to be behind a bomb explosion in Tehran on Wednesday that killed Ismail Haniyeh, one of Hamas' top leaders, while he was on a visit to the Iranian capital.
Israeli carrier El Al continues to fly as scheduled between Tel Aviv and five U.S. airports.