The U.S. government in 1983 strongly urged Prime Minister Yasuhiro Nakasone to raise Japan’s share of spending on security, according to diplomatic records declassified by Tokyo on Thursday.

The files also showed that Nakasone immediately responded to a U.S. request to contribute funds to a multilateral force operating in the Middle East.

The records reveal the beginnings of Japan’s move to shoulder some of the security burden carried by the United States, which at the time was troubled by a widening budget shortfall.

Nakasone’s commitment to proactively contribute to the Japan-U.S. alliance in his first summit with U.S. President Ronald Reagan — held just two months after the Japanese leader took office — kick-started the “Ron-Yasu” friendship that would characterize the leaders’ cordial dealings.

According to a top-secret diplomatic cable dated Jan. 19, 1983, U.S. Secretary of State George Shultz had asked Nakasone in a meeting in Washington the day prior to provide funding for a multinational force, which included U.S. and French troops, deployed to Lebanon. The country was then in the middle of a civil war.

Nakasone said, “The answer is yes,” and asked that Shultz discuss with his foreign minister the scale of the funds and under what pretext the funds should be provided, according to the cable.

Shultz also asked Nakasone for about $100 million in Japanese assistance to Yugoslavia, which was mired in a debt crisis.

The Foreign Ministry in Tokyo said it “cannot confirm” the presence or absence of any supply of funds to the multinational force, and a person who was with the ministry at the time claimed to have “no memory of being instructed to allocate the funds.”

Nakasone’s trip came as Japan decided to transfer weapons technology to the United States, in a narrow exception to its stringent policy restricting arms exports.

The “Three Principles on Arms Exports” policy, adopted in 1967, dictated that Japan would not transfer weapons to communist states, countries subject to embargoes under U.N. resolutions or those involved in international conflicts.

At his meeting with Reagan on Jan. 18 about Japan’s decision to transfer weapons technology to the United States, Nakasone said the move was a way to “persuade the (Japanese) public to return Japan to a normal course,” and Reagan welcomed that assertion, according to the file cabled the following day.

At a meeting that followed, open to officials from both countries, Nakasone said Japan and the United States “have a common destiny, and will share both our joys and our sadness.”

U.S. Defense Secretary Caspar Weinberger, who attended the meeting, praised Japan’s fiscal 1983 defense budget, which had grown from the year prior. But he urged Tokyo to raise the scale further.

Nakasone asked the Americans to understand that in an emergency, Japan would contain Soviet submarines in the Sea of Japan and prevent Soviet bombers from flying over Japan.

According to a separate document, Nakasone said at a breakfast with the owner of The Washington Post before the summit that Japan would “robustly protect the Japanese archipelago like an unsinkable aircraft carrier.”

The prime minister also said there “should be no taboo” over discussions of amending the Constitution. The foundational document, in which Japan renounces ever again waging war or possessing war potential, came into force in 1947 while Japan was under postwar U.S. occupation.

In response to the release of the records Thursday, Nakasone, now 98, said Japan’s most important diplomatic task was to build “relationships of trust” with the United States and other major powers,” given the security threat posed by the Soviet Union at the time.

In preparing for his trip, a U.S. senator had asked Japanese Ambassador to the United States Yoshio Ogasawara that Japan pay most of the costs of repairing U.S. ships protecting oil shipping routes in the Persian Gulf and $300 million associated with the deployment of U.S. fighter planes at Misawa Air Base in Aomori Prefecture, according to the documents.