South Korea has agreed to a deal to buy 40 Lockheed Martin Corp. f-35 fighter jets for $7 billion set to be delivered between 2018-2021. In March the country confirmed to choice by becoming the 10th country to choose f-35 fighter jets to replace its aging fleet of warplanes and bolster its defense against North Korea. South Korea's Defense Acquisition Program Administration said in a statement, "We have agreed to acquire 40 jets within the total budget and reflect all the terms negotiated during the 2013 competition."