At the ceremony Tuesday marking the 68th anniversary of the U.S. atomic bombing of Hiroshima, Prime Minister Shinzo Abe vowed to do whatever he can to achieve a world without nuclear arms and to offer better support to atomic-bomb survivors fighting radiation-caused health problems.

Abe also said in his speech in Peace Memorial Park near ground zero that Japan will maintain its three nonnuclear principles of not producing, possessing or allowing the entry of nuclear weapons onto its territory.

"We Japanese are the only people to have experienced the horror of nuclear devastation in war," he said in front of an estimated 50,000 people at the annual event. "We bear a responsibility to bring about a world without nuclear weapons without fail."