TOKYO, April 22 (Kyodo)—Some U.S. government officials and experts have strong concerns about Japan's plan to operate a nuclear fuel reprocessing plant in Aomori to retract plutonium while most of the nation's reactors remain shut down, a member of the government's Japan Atomic Energy Commission said Monday.

"It was an unprecedentedly severe reaction," Tatsujiro Suzuki, the commission's vice chairman, told reporters after a commission meeting, referring to U.S. officials' comments during his trip to the United States in early April.

"I think this is because the Liberal Democratic Party stands firm to uphold a policy of reprocessing spent nuclear fuel, and also because plans to operate the reprocessing plant are moving forward," Suzuki said.

Arousing U.S. concern is Japan Nuclear Fuel Ltd.'s aim to start operating its fuel reprocessing plant in Rokkasho, Aomori Prefecture, in a full-fledged manner in October.

Japan possesses a large amount of plutonium but prospects for consuming it remain unclear as most of Japan's nuclear reactors are idled amid heightened concerns over the safety of nuclear power after the 2011 Fukushima nuclear crisis.

Since the Rokkasho plant operator needs to meet new regulations of the Nuclear Regulation Authority, it is still unclear when the plant can begin operation.

Suzuki quoted U.S. Assistant Secretary of State Thomas Countryman as saying that if Japan conducts nuclear spent fuel reprocessing while its profitability remains unclear, there is a chance that Japan's international reputation may be significantly damaged.

Countryman was also quoted as saying that Japan's reprocessing work could affect Iran and other countries with nuclear ambitions.

U.S. Deputy Secretary of Energy Daniel Poneman was quoted by Suzuki as saying that he has great concern that Japan may possess a large inventory of plutonium without plans to consume it.

Japan possessed about 26.5 tons of fissile plutonium as of the end of 2012. Several kilograms of the material are said to be enough to make a nuclear weapon.

Source: The Associated Press