Many experts, well versed in defense and foreign policy, have backed a controversial plan that would allow Japan to acquire so-called enemy base strike capabilities, government sources said Sunday, but critics are likely to question giving weight to opinions of pundits who worked in the government.

Among the experts invited by the government to closed-door hearings on the issue were former high-ranking officials who said they believe possessing such capabilities is necessary, according to the sources. Details of the hearings, including the minutes, remain undisclosed.

Japanese Prime Minister Fumio Kishida (2nd from L) visits the Ground Self-Defense Force's Asaka base straddling Tokyo and Saitama Prefecture on Nov. 27, 2021. (Pool photo) (Kyodo) ==Kyodo

A review into Japan's security, including the politically sensitive issue of possessing such capabilities, comes at a time when China has been ramping up its military activities in waters near Japan, and North Korea continues to undertake ballistic missile tests.

A series of hearings -- seven in total -- involving experts in the public and private sectors was carried out by the government from January to March as part of Japan's review of three security policy papers.

The first three, carried out from January to February, centered on security and the possession of the capabilities and came ahead of the government's plan to revise the long-term guideline, the National Security Strategy, and two other key documents on defense, by the end of the year.

Prime Minister Fumio Kishida has said the government will "examine all options necessary for national defense," including the plan on Japan's acquisition of such capabilities, despite its war-renouncing Constitution.

Some critics say allowing Japan to acquire such capabilities would herald a major postwar shift from its exclusively defense-oriented policy while also marking a change in the nature of the Japan-U.S. security alliance.

During one of the hearings, participants, including Shotaro Yachi, former head of Japan's National Security Secretariat, gave their takes on the domestically debated issue of the acquisition of such capabilities, the sources said.

Among them was a call for Japan to make a drastic policy change, as it did when it enacted security legislation in 2015 that expanded the scope of the Japanese Self-Defense Forces' operations overseas, according to the sources.

In another hearing, a participant underscored the need for the SDF to fill any gap that may arise until U.S. troops arrive during contingencies.

Participants also included former Defense Minister Satoshi Morimoto, former national security adviser Shigeru Kitamura and Ryoichi Oriki, former chief of the Joint Staff.

Experts in the private sector were also invited to the hearings from February to March to discuss specific themes such as space and regional affairs, including North Korea and China.