Japan is considering scrapping its plan to procure U.S.-made long-range anti-ship missiles (LRASM) with standoff capabilities for the Air Self-Defense Force's F-15 fighter jets, government officials have said.

The plan to change its policy is due to ballooning costs, the officials, who declined to be named as a formal decision has not yet been made, said Saturday.

The acquisition of the Lockheed Martin missiles is aimed at giving the ASDF the capability to strike from outside an enemy's threat range.

At a time of increasing assertiveness by China around Japanese territories, the Defense Ministry has said the missiles, which are said to have a range of 900 kilometers, are necessary for boosting Japan's defense capabilities around the Nansei Islands, a chain stretching southwest toward Taiwan.

With the likely policy change, the government will also consider reducing from 70 the number of the ASDF's fleet of F-15 aircraft it is planning to upgrade, according to the officials.

The ASDF has about 200 F-15s and the LRASM is one of the two U.S.-made cruise missiles it plans to mount on the fighter jets.

The other is Lockheed Martin's air-to-surface standoff missile called JASSM.

By forgoing the acquisition, the government has estimated it will save tens of billions of yen. In the fiscal 2021 budget, the government did not include spending on upgrading the fighter jets, believing it necessary to prioritize negotiations with the U.S. side to reduce costs.

For the upgrade to enable the fighters to carry the LRASM, the initial cost presented by the U.S. side has increased to nearly ¥240 billion ($2.2 billion) from about ¥80 billion, partly because supplies of necessary electrical components are running short.