Trump: 'Iran Made a Very Big Mistake'

President Donald Trump appeared to threaten Iran on Twitter Thursday morning after the Iranian Revolutionary Guard shot down a U.S. drone.

"Iran made a very big mistake!" Trump wrote without immediate elaboration.

His statement also comes at a time of increasing tensions between the U.S. and Iran in the wake of Trump's decision to withdraw from Tehran's nuclear deal a year ago.

White House press secretary Sarah Sanders said Trump was briefed Wednesday night and again Thursday morning about the drone incident.

She said  the administration also will keep in touch with lawmakers on Capitol Hill.

American and Iranian officials are disputing the circumstances of the incident.Iran's Revolutionary Guard said it shot down the drone over Iranian airspace. The U.S. military is calling the downing an "unprovoked attack" and said it occurred over international airspace in the Strait of Hormuz.

This report includes material from Reuters and The Associated Press.