TOKYO - Japan's prime minister sternly reprimanded the nation's defense minister for saying the atomic bombings of Hiroshima and Nagasaki were an inevitable way of ending World War II, and asked him Monday to refrain from making similar remarks.

Japan's Defense Minister Fumio Kyuma answers reporters questions after meeting with Prime Minister Shinzo Abe at the prime minister's official residence in Tokyo Monday, July 2, 2007. [AP]

Prime Minister Shinzo Abe told Defense Minister Fumio Kyuma to "strictly refrain from making remarks that cause misunderstanding," said chief Cabinet spokesman Yasuhisa Shiozaki.

"It is necessary for Cabinet ministers to pay constant and careful attention to what they say and do so that they do not cause any public misunderstanding," Shiozaki said.

Kyuma's comments offended survivors of the bombings who believe the use of atomic weapons was excessive, but the minister is not expected to resign.

"I understand he will carry out his responsibility as a Cabinet minister in consideration of the prime minister's stern warning," Shiozaki said.

On Aug. 6, 1945, the US dropped a bomb nicknamed "Little Boy" on Hiroshima, killing at least 140,000 people in the world's first atomic bomb attack. Three days later it dropped another atomic bomb, "Fat Man," on Nagasaki, where about 74,000 are estimated to have been killed.

Japan, which had attacked the United States at Pearl Harbor, surrendered on Aug. 15, 1945.

"I understand that the bombing ended the war, and I think that it couldn't be helped," Kyuma said in a speech at a university in Chiba, just east of Tokyo. Part of the part speech Saturday was aired by public broadcaster NHK.

Kyuma, who is from Nagasaki, said the bombing caused great suffering in the city but said he did not resent the US because the bombs prevented the Soviet Union from entering the war with Japan, according to Kyodo News agency.

The remarks were quickly criticized by atomic bomb victims.

Nagasaki Mayor Tomihisa Taue called the bombings the "indiscriminate massacre of ordinary citizens" and the opposition Social Democratic Party called for Kyuma's dismissal.