Dutch airline KLM on Friday said it has suspended flights over the Strait of Hormuz as a precautionary measure after a U.S. drone was downed by Iran.

"We closely follow all developments that may be related to the safety of airspace 24/7 and we organize the operation in such a way that the safety of the flights is guaranteed," read a statement by the airline.

The U.S. said on Thursday that an RQ-4A Global Hawk unmanned aircraft was shot down by Iran while flying over international waters. However, Tehran said the drone was on a spy mission and had entered the Iranian airspace.