June 13 (Reuters) - The U.S. State Department has

approved the possible sale of advanced medium-range air-to-air

missiles and related equipment to the Netherlands for an

estimated cost of $678 million, the Pentagon said in a statement

on Thursday.

The principal contractor will be RTX Corp ( RTX ), the

statement said. The Netherlands has requested to buy 174

Advanced Medium-Range Air-to-Air Missiles-Extended Range

(AMRAAM-ER) and four AMRAAM-C8 guidance sections, among other

items, it said.