MANILA, Aug. 17 (Xinhua) -- Philippine Defense Secretary Delfin Lorenzana urged the United States on Friday to return the Balangiga bells the American soldiers carted away from a church in the central Philippines during the 1901 Philippine-American war.

"We call on the American people not to allow the bells to serve as trophies for atrocities that were committed by both sides on Philippine soil a very long time ago," Lorenzana said in a statement.

Lorenzana said "the return of the Balangiga bells will be a strong indicator of the sincerity of the Americans in forging a lasting relationship with the Filipino people and truly symbolic of what their government has referred to in the past as an ironclad alliance between our two countries."

Lorenzana issued the statement after news reports came out that three U.S. lawmakers have voiced "strong disapproval" to return the bells to the Philippines. The U.S. embassy in Manila said U.S. Defense Secretary Jim Mattis has signed documents favoring the return of the bells.

Lorenzana thanked Mattis "for his effort in seeking the return of the bells to our country."

"We do hope that the U.S. government will follow through with their commitment and that it will become a reality soon," Lorenzana added.

Lorenzana reminded the Americans that both the Philippines and the U.S. had suffered from that war.

He referred that period as "a dark chapter in the shared history of our peoples, which should never be allowed to happen again."

Meanwhile, the Philippine Department of Foreign Affairs said it has not been officially informed about Mattis' decision.

President Rodrigo Duterte has repeatedly lambasted the U.S. for keeping the bells which he said belongs to the Philippines, saying they are from a "sentimental part of the journey towards nation-building."

Filipinos used the Balangiga bells as the signal to launch a surprise attack against American troops on Sept. 28, 1901 stationed in Balangiga, a town in eastern Samar province in central Philippines.

The attack killed more than 70 Americans, as well as thousands of Filipino soldiers and locals after the foreign troops fought back. They took three bells from the Balangiga Church to serve as spoils of war.