An that damaged the International Airport in June made it impossible for the United Nations to fly in aid deliveries to needy Syrians for around two weeks, the said on Wednesday.
Commissioner Lynn Welchmann told reporters in Geneva that the Israeli strike "led to considerable damage to infrastructure and the closure of the airport for nearly two weeks or 13 days".
That "meant the suspension of UN deliveries of humanitarian assistance which is extremely serious," she said.
Earlier this year, Russia blocked aid to Idlib and vetoed a UN Security Council resolution that would have extended cross-border aid to Syria by one year.
Syria, like many Middle East nations, has dual-use airports that include civilian and military sides.
Israel has said it will target Iranian weapons shipments to Syria, targeted as part of a long-running shadow war between Tehran and Israel.
Iran, as well as Lebanon’s allied Hezbollah militant group, has been crucial to Assad remaining in power since the war began in his country amid the 2011 Arab Spring.