(Adds details on P-8 Poseidon aircraft, Patriot missiles)
WASHINGTON, Sept 13 (Reuters) - The U.S. State Department has approved possible military sales worth $2.6 billion to South Korea, including six P-8A Poseidon maritime reconnaissance aircraft and 64 Patriot anti-ballistic missile weapons, the Pentagon said on Thursday.
The Boeing-made Poseidon aircraft, which are used for hunting submarines and conducting maritime reconnaissance, are worth up to $2.1 billion, the Pentagon's Defense Security Cooperation Agency (DSCA) said.
The South Korean procurement agency Defense Acquisition Program Administration (DAPA) said in June it had decided to buy the P-8 Poseidon aircraft.
At the time, the contract was worth around $1.71 billion. Thursday's DSCA authorization included training, logistics, support equipment and services that could affect the price.
U.S. ally South Korea is engaged in talks with North Korea on improving relations and the United States is involved in its own diplomatic efforts with North Korea on denuclearisation of the Korean Peninsula. Washington has put pressure on North Korea via sanctions to give up its nuclear weapons program.
The Patriot anti-missile systems, made by Lockheed Martin Co , are to defend against ballistic missiles and will cost $501 million, the Pentagon said.
The Republic of Korea requested 64 Patriot Advanced Capability-3 (PAC-3) Missile Segment Enhancement (MSE) Missiles.
DSCA said the proposed sales, which were notified to Congress on Thursday, will help South Korea improve its missile defense capability and support U.S. national security objectives by enhancing Seoul's naval capabilities. (Reporting by David Alexander and Mike Stone; Editing by Doina Chiacu and Grant McCool)