A former British ambassador to Japan expressed in an article his concerns that Japan's ruling Liberal Democratic Party's leaders could threaten its long-term national interests through policies that could lead to a more autocratic and nationalist regime, a local newspaper reported on Tuesday.

Hugh Cortazzi, British ambassador to Japan from 1980 to 1984, wrote in Japan Times, an independent English-language newspaper, that the Abe administration is putting more pressure on media to support his policies.

"NHK, which should be independent, has become a government mouthpiece. The kisha club (press club) system, which is used to feed government information to the media, has been used to promote self-censorship by the implied threat of being excluded from access. A vendetta against Asahi Shimbun seems to have been at least partly successful," Cartazzi said.

The Special Secrecy Law, which took effect in 2013, was passed "without adequate parliamentary scrutiny and contains provisions that could be misused to limit freedom of speech," he wrote.

"Anyone familiar with the spy mania of prewar Japan must be concerned about the dangers from this piece of legislation."

Cortazzi slammed the prime minister's historical revisionism as "a major cause for concern," saying the facts of the Nanjing Massacre and "comfort women", as well as slave laborers who died building the Burma-Siam railway, have not been forgotten in the victimized countries, "even if Japanese school textbooks do not mention these facts."

"As the 70th anniversary of the end of the war approaches, any attempt by Abe to dilute the Murayama and Kono statements or to deny historical facts will be damaging to Japan's reputation in the world and to its national interests," he wrote.