Several major airline companies, from the U.S. and Europe to Asia announced they have suspended flights to Israel and Lebanon, citing security concerns following recent developments in the Middle East.

The decision follows Wednesday’s assassination of Hamas political chief Ismail Haniyeh in Tehran. Expected retaliation from Iran against Israel has heightened security risks, impacting airline operations.

United Airlines, which operates 14 weekly flights between New York and Israel, has suspended flights to Israel until Aug. 6.

The U.S. Delta Airlines also suspended flights to Israel, and British Airways canceled its flights to the country on Wednesday.

Swiss International Air Lines suspended flights between Zurich and Tel Aviv until at least Aug. 8, citing the safety of crew and passengers. Also, the suspension of Zurich-Beirut flights, initially set to end on July 29, has been extended to Aug. 12.

German airline Lufthansa announced it had suspended flights to Beirut and Tel Aviv until Aug. 8 and Aug. 12, respectively, due to security concerns.

The airline said it would monitor the situation on the ground to determine when flights can resume.

Air India also canceled its flights to Tel Aviv until Aug. 8, citing security concerns.

ITA Airways, Italy’s flag carrier, announced that flights to and from Tel Aviv are suspended until Aug. 6 "due to geopolitical developments in the Middle East and to ensure the safety of its passengers and crews."

Poland’s national airline LOT canceled eight flights to Lebanon and Israel scheduled for Aug. 3-4, according to Polish news agency PAP.

Dutch airline KLM also canceled all its flights to and from Israel until Oct. 26.

Aegean Airlines and Condor Airlines have also earlier suspended flights from Athens to Beirut until Aug. 1 due to regional tensions.

Singapore Airlines (SIA) said it would avoid Iranian airspace due to rising Mideast tensions.

The suspensions come amid rising tensions and the potential for a broader conflict between Iran and the Lebanese Hezbollah group on one side and Israel on the other.