SEOUL, South Korea (CNN) -- More than a year ago, the groundbreaking for a nuclear power plant in Kumho, North Korea, was seen as the beginning of the end of that country's suspected nuclear-weapons program.

North Korea had agreed to suspend its plutonium-producing nuclear ambitions in return for two light-water nuclear reactors and a steady supply of fuel oil. But now, that agreement seems to be in trouble.

The Korean Peninsula Energy Development Organization (KEDO), the international consortium set up to build the reactors, says the project is critically short of money. KEDO officials also say they need additional contributions of nearly $30 million to complete the promised delivery of heavy fuel oil Ð another part of the agreement -- by October 21.

What has thrown a wrinkle into the deal is North Korea's recent firing of a suspected long-range missile over Japanese territory. The North Koreans insist that the device was used to launch a satellite into space, but U.S. and Japanese officials are skeptical of that claim.

In response, Japan suspended a cost-sharing deal to build the reactors. Full-scale construction had been scheduled to begin next year. And the U.S. Congress balked at providing money for the U.S. share of the fuel oil.

However, on Wednesday, the White House announced that President Clinton, using his presidential authority, had decided to commit $15 million toward the oil purchase.

With that contribution, U.S. State Department spokesman James Foley said North Korea will have received 366,000 metric tons (402,600 tons) of heavy fuel oil out of the 500,000 metric tons (550,000 tons) originally promised.

He said efforts were being made to obtain the funds necessary to provide the rest of the oil.

But even if Japan and the United States eventually honor their end of the deal, new questions have arisen about whether North Korea is really serious about abandoning its nuclear weapons program.

North Korea has denied recent reports that it was building a secret underground nuclear facility. But the United States has called for outside inspections of the suspected site.

Seoul Bureau Chief Sohn Jie-Ae and Reuters contributed to this report.