LONDON -- The dramatic suicide by Japanese writer and nationalist Yukio Mishima after his failed attempt to foment a coup in 1970 triggered British concern about a revival of militarism in Japan, according to 30-year-old declassified British documents released on New Year's Day.

The papers, dispatched by the British Embassy in Tokyo immediately after Mishima's death to the Foreign and Defense ministries in London, pointed to Mishima's appeal against the Nonproliferation Treaty, which took effect only eight months before his failed effort to stage a coup.

"The most interesting part of (Mishima's) appeal may be the reference to the Nonproliferation Treaty," the embassy wrote in one of the documents, suggesting a close watch be kept on how rightists reacted to the treaty.