On Sunday I reported that Israel Air Force fighter jets and Israel Navy warships were participating in a joint drill in the Mediterranean Sea with the U.S. Sixth Fleet and the Greek military, called "Noble Dina."

The report was based on two articles published in the Greek press, which presented the joint exercise as a message to Turkey.

On Tuesday, I was contacted by a senior U.S. official who is familiar with the details of the exercise. The official sought to clarify that the drill was not directed against Turkey or any other state in the region, and is not meant to simulate any realistic scenario.

"The exercise has no scenario. It is primarily anti-submarine warfare, with maritime domain awareness, which means sharing information about the location of vessels at sea, damage control, anti-terrorism and force protection, anti-piracy and medical training," the official said.

Noble Dina began in 1998 as a bilateral exercisebetween the American and Israeli navies.Since 2009, the exercise has been trilateral, with the participation of the U.S., Israel and Greece.

Greek media reported that the joint drill replaced a previous drill called "Reliant Mermaid," in which Israel, the U.S. and Turkey participated. The official said that the two drills are not connected, and that one did not replace the other.

"Although the exercise is considered a trilateral maritime exercise, in 2010 and 2011 it proceeded as a bilateral exercise in Turkey's absence," said the official. He added that the drill takes place every year in August.