NATO is prepared to address any threat and will always do what is necessary to defend all allies, a NATO official said on Wednesday in response to questions about a report in the Financial Times that Iran has allegedly weighed attacking US military targets in Europe should Donald Trump escalate the war.

"As demonstrated earlier this year when NATO air defenses successfully intercepted ballistic missiles heading to Turkey from Iran on four separate occasions, our deterrence and defense posture is strong and effective," the official said.

This is a developing story.