MANILA, Sept. 13 (Xinhua) -- The Philippines has expressed unhappiness with U.S. lack of interest in investing in the Philippine government's flagship infrastructure project to develop the Clark Freeport Zone, a former U.S. military airbase, into a big metropolis.

During his recent meeting with Manisha Singh, U.S. assistant secretary of state in Manila, Finance Secretary Carlos Dominguez "questioned the absence of American investors" in the Philippine government's flagship infrastructure project to develop the Clark special economic zone, said a statement released by the Department of Finance on Thursday.

Dominguez said the absence of American investors in the bidding for the New Clark City development project could indicate that American investors "have no interest" in taking part in the Philippines' economic emergence that is anchored on its massive "Build, Build, Build" program.

Dominguez pointed out that the Philippine government, which is funding the transformation of the former U.S. military base into New Clark City, had announced the public bidding for the project before the international community, but no American companies took part in the bidding process.

Dominguez said some American companies have submitted bids, but only for the design component of the New Clark City project.

"Maybe they don't have an interest here," Dominguez told Singh.

Singh, who handles U.S. State Department's economic and business affairs, said she will speak with leaders of U.S. infrastructure companies to tell them about the immense investment opportunities in the "Build, Build, Build" program of the Duterte administration.