U.S. President Barack Obama's planned visit to the Japanese city of Hiroshima is aimed at honoring the memory of not only Japanese victims of the 1945 U.S. atomic bombing, but also all innocents lost during the war, the White House said Thursday.

Obama is scheduled to visit Hiroshima on May 27 in what the White House described as a "historic" trip that will make him the first sitting American president to do so since the U.S. dropped an atomic bomb in the city to end World War II.

White House officials said Obama wants to use the visit to "highlight his continued commitment to pursuing the peace and security of a world without nuclear weapons" and "to honor the memory of all innocents who were lost during the war."

But the planned visit raised concern that it could dilute Japan's wartime aggression by making the country look like a victim, even though U.S. officials said the visit shouldn't be interpreted as an apology and Obama won't revisit the decision to use the atomic bomb.

On Thursday, White House Asian Affairs spokesman Myles Caggins reaffirmed that the visit is aimed at honoring not only innocent Japanese A-bomb victims, but also all innocents killed in the war.

"President Obama's visit is designed to honor the memory of all innocents lost in World War II, including at Hiroshima," Caggins told Yonhap News Agency.

As many as some 140,000 were killed in the Hiroshima bombing on August 6, 1945, and some 20,000 of them were Koreans. The U.S. dropped another atomic bomb in the city of Nagasaki three days later, leaving as many as 80,000 people dead, and some 10,000 of them are believed to be Koreans.

Whether Obama would visit Hiroshima on the sidelines of a Group of Seven summit has been a focus of attention since Secretary of State John Kerry made a landmark visit to the city last month and said he would convey to Obama what he saw in Hiroshima and "how important it is at some point to try to get here."

Obama has sought to make the initiative for building a nuclear-free world a key legacy of his presidency, launching the Nuclear Security Summit of world leaders aimed at reducing the stockpile of fissile material and keeping it out of the hands of terrorists. (Yonhap)