A U.S. plan to boost production of Patriot surface-to-air missiles, which Ukraine uses to counter Russian attacks, using Japanese factories is being delayed by a shortage of a key Boeing part, four sources familiar with the matter said. Reuters.

Japan’s Mitsubishi Heavy Industries (MHI) 7011.T, which currently produces about 30 PAC-3 missiles annually under a license from defense contractor Lockheed Martin LMT.N , may increase production to about 60 missiles, two Japanese government officials and two industry sources said. Reuters.

The U.S. wants to increase global production as quickly as possible from about 500 to more than 750 Patriot missiles a year, a source familiar with the program said. However, officials and industry sources said no expansion in Japan would be feasible without a larger inventory of the missiles’ seekers, which are crucial to guiding them through the final stages of flight.

“It could take years before MHI can increase production” because of the shortage, one of the industry sources said. Reuters.

The production slowdown in Japan underscores Washington’s challenges in incorporating global allies into its supply chains. Boeing is expanding its U.S. Seeker factory to increase production by 30%, but it won’t be operational until 2027.

Lockheed Martin plans to increase U.S. Patriot interceptor production from 500 to 650 by 2027, with each costing about $4 million. However, to expand Japan’s PAC-3 missile production to more than 60 units per year, Mitsubishi Heavy Industries (MHI) would need to increase its capacity.

In its 2022 plan to double military spending, the Japanese government announced that it would provide financial aid to defense companies that want to expand their production. However, these subsidies are limited to equipment intended for the Japan Self-Defense Forces and do not cover exports.

As a result, Mitsubishi Heavy Industries (MHI) or the United States would have to finance the construction of a new PAC-3 plant, which could cost tens of millions of dollars or more, one of the Japanese government sources said.

“The Indo-Pacific is a major area of ​​focus for the U.S. and our allies and strategically placed capabilities in the region are critical to supporting deterrence and maintaining readiness,” Lockheed Martin said in an email, referring questions about Japan’s PAC-3 production to the Japanese and U.S. governments and MHI.

A $4.5 billion contract with the U.S. military in June will boost production of Patriot missiles and seekers. Japanese and U.S. defense and foreign ministers are meeting in Tokyo to discuss improving industrial cooperation, with the Patriot project a major focus. However, supply chain bottlenecks continue to challenge U.S. efforts to supply Ukraine with needed munitions and air defense systems.

Ukraine needs 25 Patriot systems for airspace protection: Zelensky

Ukrainian President Volodymyr Zelensky said Monday that Kiev needs 25 Patriot air defense systems to fully protect its airspace. However, he did not disclose how many Patriot systems the country currently possesses.

“If I say how many more we need, it becomes clear how many we already have. I can tell you how many Patriots we need… We need 25 systems to completely cover the skies over Ukraine,” Zelenskyy told reporters.

Zelensky also said that in addition to the US-made Patriots, Ukraine also needs additional Western air defense systems.

For months, Ukraine has been asking for seven additional Patriot systems to defend against Russian attacks as the war enters its second and a half year.

NATO chief Jens Stoltenberg urged allies to continue their support for Kiev, warning that a Russian victory would pose the “greatest risk” to the US-led military bloc.

“The outcome of this war will determine global security for decades to come,” Stoltenberg stressed.

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