China added 20 Japanese entities on Monday to its export control list for dual-use items, preventing Chinese firms from selling to them without prior approval, citing Tokyo's ambitions for "remilitarisation".
The action, Beijing's latest in a series of export curbs targeted at Tokyo, was aimed at limiting Japan's "new type of militarism" as well as its nuclear ambitions, the Chinese commerce ministry said in a statement.
Japan's defence ministry did not immediately respond to a request for comment.
Ties between China and Japan have been strained since late last year after sensitive Taiwan-related remarks by Japanese Prime Minister Sanae Takaichi and Tokyo's decision to increase defence spending, prompting Beijing to begin imposing export controls on dual-use items in January.
"China's lawful action of listing only targets a small number of Japanese entities, the relevant measures apply only to dual-use items, which does not affect the normal economic and trade exchanges between China and Japan," the ministry said, reassuring that law-abiding Japanese entities operating "in good faith" need not worry.
"Our government has filed a stern protest and demanded the withdrawal of the steps," Japanese Chief Cabinet Secretary Minoru Kihara said at a regular news conference, describing the measures as "absolutely unacceptable and extremely regrettable."
The 20 entities include Japan's National Institute for Defense Studies, as well as six subsidiaries of Mitsubishi Heavy Industries (MHI), Japan's largest defence contractor; four units of missile and radar maker Mitsubishi Electric ; and two subsidiaries of aircraft and submarine builder Kawasaki Heavy Industries, according to the ministry's notice.
Spokespeople for MHI and Mitsubishi Electric said they were assessing the announcement but declined to say whether it could affect their businesses.
Dual-use items are goods, software or technology with potential military or weapons-development applications.
Chinese exporters are prohibited from selling to the entities while foreign organisations and individuals are prohibited from transferring or supplying dual-use items originating in China to them, effective immediately.
The ministry also put 20 other Japanese entities on a watchlist for which it could not verify the end users or final use of dual-use items exported to them.
The watchlist deters trade with those entities but requires exporters applying to do so to provide a risk assessment report and a written commitment not to use dual-use items for any purpose that would enhance Japanese military strength.