TOKYO (Reuters) - Prime Minister Shinzo Abe’s visit to Pearl Harbor this month may not be the first by a sitting Japanese premier but will be the first with a U.S. president, his top government spokesman said on Thursday, trying to clarify confusion over the trip.

Japanese Prime Minister Shinzo Abe gestures during a press conference in Buenos Aires, Argentina, November 21, 2016. REUTERS/Agustin Marcarian

Abe announced on Monday he would join President Barack Obama on a Dec. 26-27 visit to the site of the Japanese surprise attack 75 years ago that drew the United States into World War Two.

A foreign ministry official said on Monday that Abe would be the first incumbent Japanese leader to visit.

But media this week said that back in September 1951 then-Prime Minister Shigeru Yoshida stopped by Pearl Harbor en route from San Francisco.

When asked about this, Chief Cabinet Secretary Yoshihide Suga told reporters the government could not confirm exactly where Yoshida visited.

“Then-prime minister Yoshida visited Honolulu in 1951 and at that time he honored the war dead at the National Memorial Cemetery of the Pacific,” Suga said.

“The scope of Pearl Harbor is broad and whether Prime Minister Yoshida visited there or carried out some ceremony cannot be confirmed.

“At any rate, the Arizona Memorial in Pearl Harbor was not built then and Prime Minister Abe will be the first incumbent prime minister to pray for the war dead there,” Suga said, referring to a memorial for U.S. sailors and Marines killed in the attack.

“He will also be the first to do so with an American president.”

Abe’s visit to Pearl Harbor will come seven months after Obama became the first serving U.S. president to visit the Japanese city of Hiroshima, where the United States dropped an atomic bomb in the closing days of the war in 1945.

The two leaders hope to showcase the strength of the security alliance between the two former wartime foes.