U.S. wants to boost Japan nuclear umbrella: paper

TOKYO (Reuters) - The United States plans discuss with Japan how to boost the nuclear deterrent it provides for its Asian ally, a senior U.S. official was quoted as saying on Friday amid regional tensions over North Korea's nuclear and missile tests.

Kurt Campbell, the assistant secretary of state for East Asian and Pacific Affairs, said Washington and Tokyo planned to hold regular talks on boosting what is dubbed the "nuclear umbrella," starting on Saturday, the Nikkei newspaper said.

His comments come two months after Japan's unpredictable neighbor North Korea raised tensions in the region by carrying out its second nuclear test.

But talk of stepping up defenses in Japan could raise hackles in other parts of Asia, where many suffered under Japanese militarism before and during World War Two.

Campbell is currently visiting Tokyo for talks ahead of a general election next month that polls show will likely oust the long-ruling Liberal Democratic Party (LDP) and bring in the opposition Democrats, who say they want more independence from Washington.

Japan, the only country to have suffered nuclear attacks, has repeatedly said it will stick to three principles on nuclear weapons -- not to possess, produce or allow them to be brought into the country.

But the renewed threat from North Korea has sparked discussion as to whether Japan should re-think the third principle and allow the United States to bring nuclear weapons into Japanese ports.

Japanese media reports have said that Tokyo signed a secret agreement with the United States to allow port calls by ships carrying nuclear weapons. But government officials have denied the existence of such an agreement.

(Reporting by Isabel Reynolds; Editing by Alex Richardson)