Publicity about Pyongyang's nuclear and missile tests may have influence a poll that found U.S. citizens consider North Korea a bigger security threat than China.

Some 75 percent of Americans polled called North Korea the most significant military threat next to the Middle East, according to a joint survey by Gallup and Japan's Yomiuri Shimbun. The Middle East ranked as the top threat at 78 percent. China was listed third at 44 percent, indicating warming ties between the two giants.

Contrary to such public perceptions, the Pentagon's annual reports have monitored China as a rising military challenger in the Post-Sovet world with resources that dwarf those of any Middle Eastern state and of North Korea.

North Korea detonated a nuclear device on Oct. 9, following a series of missile launches in July, including long-range weapons.

Some analysts raised the possibility that North Korea would conduct a second nuclear test or launch a ballistic missile equipped with a nuclear warhead and having the capability of reaching the continental United States.

Yomiuri said 71 percent of U.S. respondents were concerned that Japan and South Korea would be engaged in a nuclear buildup following North Korea's nuclear test.

According to the Yomiuri-Gallup survey, about 80 percent of Japanese respondents ranked North Korea as the biggest threat to their country. About 41 percent of the Japanese polled said they trusted the United States, while 76 percent of U.S. respondents said they trusted Japan. The joint survey of about 1,000 adults in each nation was conducted via telephone in mid-November.

Earlier, Seoul's Korea Institute for Defense Analyses cited its poll showing 38 percent of South Koreans consider China to be the biggest security threat to their country, followed by Japan. North Korea ranked third, reflecting the continuing mood of reconciliation.