South Korea will buy Taurus KEPD 350 cruise missiles for its Lockheed/Boeing F-15K Strike Eagle fighters, the first strategic weapon purchase not from an American supplier, Yonhap News Agency reported.

The government's Defense Acquisition Program Administration approved the plan to buy the air-to-ground missiles that have a 300-mile range.

The number of missiles and proposed budget haven't been confirmed, defense officials said.

The only long-range missiles in the air force's inventory are about 40 SLAM-ER missiles with a range of about 180 miles, Yonhap said.

Subsonic SLAM-ER expanded response missiles were developed from the U.S. Navy's Harpoon anti-ship missile.

Seoul had expressed interest in the joint air-to-surface standoff missile manufactured by Lockheed Martin. But the Pentagon hasn't approved sales of the 230-mile-range missile, which is classified as a strategic weapon, to South Korea.

The Taurus KEPD 350 is made by German-based Taurus Systems, a partnership between LFK (EADS/MBDA) and Saab Bofors Dynamics from Sweden.

The Taurus has a 1,060-pound warhead capable of penetrating more than 18 feet of reinforced concrete with an error rate of about 9 feet.

The Taurus purchase announcement follows problems last year when South Korea attempted to mount examples of the JASSM weapons to an F-15K, The Korea Times reported at the time. The newspaper quoted a senior South Korean procurement official as saying the JASSM missiles would need modifications to its casing or wings if it were to fit under the aircraft, but this would cost money and take more time to ready the weapon for deployment.

"To install the JASSMs in both wings of the F-15K, either F-15K's pylon or the JASSM's upper wing should be modified, but it would cost a lot," the official said.

But the JASSM could cost less than the Taurus, Korea Times reported in December 2011.

A National Assembly official said the government had set aside about $343 million to procure 177 air-to-surface missiles.

The official also warned delays by U.S. authorities to authorize export of JASSM weapons to South Korea could mean the more expensive but accessible Taurus would be chosen.

"JASSM is much cheaper and easier to integrate with the existing fleet of its American aircraft. But South Korea may have no other alternative but to choose the Taurus if the U.S. Congress continues to delay the authorization for the export of JASSM," the official said.