LONDON — Ambassadors and foreign ministers from European Union countries met on Sunday via video, both to assess the situation and begin planning the evacuation of European citizens trapped in Gulf states because of the closure of airports and airspace.

After that meeting, the bloc's 27 member nations said parties involved in the conflict should attempt to contain it, and adhere to international law.

The EU's foreign policy chief, High Representative of the European Union for Foreign Affairs and Security Policy Kaja Kallas, said: "We call for maximum restraint, protection of civilians, and full respect of international law, including the principles of the United Nations Charter, and international humanitarian law."

The EU added in a separate statement that the conflict "must not lead to an escalation that could threaten the Middle East, Europe, and beyond, with unpredictable consequences, also in the economic sphere".

Spain's Prime Minister Pedro Sanchez went further, saying the US-Israeli attack on Iran "contributes to a more uncertain and hostile international order".

After Sunday's meeting of EU foreign ministers and ambassadors, the bloc's top officials and politicians had planned to reconvene in Lefkosia, Cyprus on Monday morning but the gathering was postponed after a suspected Iranian drone attack on the UK's RAF Akrotiri airbase on the island the night before.

Before the incident, UK Prime Minister Keir Starmer said the US would be able to use British bases for preemptive strikes on Iranian missile sites, to stop Iran attacking neighboring countries.

Hundreds of flights throughout the Middle East were canceled on Monday due to the conflict, with airports, including Dubai's, which describes itself as the world's busiest international hub, closed for a third consecutive day.

The closures led to 2,800 canceled flights on Saturday and 3,156 cancellations on Sunday. Some cruise ship companies have also suspended or adjusted trips because of the situation.