Japan's Prime Minister Shinzo Abe attends a ceremony commemorating the 70th anniversary of the 1945 atomic bombing of the city, at Nagasaki's Peace Park in Nagasaki, western Japan, August 9, 2015. Reuters

TOKYO (Reuters) - Japanese Prime Minister Shinzo Abe on Sunday marked the 70th anniversary of the atomic bombing of Nagasaki by renewing his commitment to a nuclear weapons free Japan, following criticism for not making the same pledge on the anniversary of the Hiroshima bombing last week.

"As the only nation in the world to have suffered a war-time nuclear attack, I have renewed my resolve to play a leading role in pursuing a world without nuclear weapons and maintain the three non-nuclear principles," Abe said in Nagasaki Peace Park.

The "three non-nuclear principles" are Japan's long-standing policy of not possessing or producing nuclear arms and not letting others bring them into the country.

Japan's defense minister triggered a new row over controversial security legislation on Wednesday when he said the bills under consideration by parliament would not rule out the military transporting the nuclear weapons of foreign forces.

Abe's cabinet adopted a resolution last year reinterpreting the pacifist constitution, drafted by Americans after World War Two, to let Japan exercise collective self-defense, or defend an ally under attack.

The unpopular bills have already passed the lower house and Abe's ruling bloc has a majority in the upper house as well. But surveys show a majority of voters are opposed to what would be a significant shift in Japan's defense policy.

Japanese media reported that Abe will not visit Tokyo's controversial Yasukuni shrine for the war dead on Aug. 15, which marks the 70th anniversary of Japan's surrender to the Allies in World War Two.

Abe is a regular visitor to the shrine and his appearances often spark ire from Asian neighbors such as China and South Korea which came under Japanese occupation.

Even if the premier stays away from Yasukuni, he may still come under scrutiny if he omits an apology in a statement expected to be released later this week marking the 70th anniversary of Japan's defeat.

Abe has said the statement will express "remorse" for Japan's war-time actions but domestic media reported over the weekend that the word "apology" will not be included.

Abe's remarks are being closely watched by China and South Korea, where bitter memories of Japan's wartime occupation and colonization run deep, and by Tokyo's close ally Washington.

(Reporting by Shinichi Saoshiro; Editing by Michael Perry)