U.S. and Japanese defense ministers have agreed to deploy another X-band missile defense radar in Japan, U.S. Defense Secretary Leon Panetta said Monday, Sept 17, AFP reported.

The move is designed to counter the threat posed by North Korea's missile arsenal, he told reporters during a joint press conference with his opposite number in Tokyo.

"The purpose of this is to enhance our ability to defend Japan. It's also designed to help forward-deployed U.S. forces," Panetta said. "It also will be effective in protecting the US homeland from the North Korean ballistic missile threat."

Around 47,000 U.S. troops are stationed in Japan, many of them on the far southern island chain of Okinawa. Japan already has one X-band radar at Shariki base in Tsugaru City, in the far north of the main island of Honshu.

A U.S. team is now on the ground looking for a site to locate the radar, likely in southern Japan, a U.S. defense official said earlier.

Officials insisted the powerful early warning radar was not directed at China but solely designed to counter North Korea.

"This is not about China," the official said.

Pyongyang carried out a failed rocket launch in April in what it said was an attempt to put a satellite into orbit.

But the UN Security Council strongly condemned the exercise as breaching a ban on the testing of ballistic missile technology, and tightened sanctions.

The additional radar frees up U.S. naval Aegis ships, which have been operating near Japan to help detect any potential incoming missiles, the official said.