A US program to keep Russian weapons from providing nuclear expertise to terrorists has been financing Russian research institutes that separately have been helping Iran build its new nuclear power reactor, a congressional committee has learned.

Democratic Rep. John Dingell, chairman of the House Energy and Commerce Committee, raised questions about the program and its possible link to Iran on a letter Wednesday to Energy Secretary Samuel Bodman, citing information the committee received from Russian sources.

"It is troubling that DOE would subsidize or otherwise support Russian institutes providing technology and services to the Iranian nuclear program," Dingell wrote in the letter also signed by Democratic Rep. Bart Stupak, chairman of the panel's investigations subcommittee.

The two congressmen asked the Energy Department to provide information whether specific scientists benefiting under the program were involved in any Iranian reactor work.

The National Nuclear Security Administration, which oversees to assistance program, said it was reviewing all the projects for any possible Iranian link.

"We are confident that none of the projects cited by the House committee, or any of the department's scientist engagement projects with Russia, support nuclear work in Iran," said John Broehm, an NNSA spokesman. "We take all measures necessary to ensure that neither money nor technology falls into the hands of countries of concern."

Iran has said the 1,000-megawatt Bushehr power plant, the country's first nuclear reactor, will begin operating this summer after receiving from Russia nearly all of the nuclear fuel it needs to operate.

The Dingell letter follows a hearing last month by the committee into the US economic aid program that began after the breakup of the former Soviet Union to help Cold War-era Russian scientists find jobs and make it less likely they would sell nuclear information or otherwise help terrorists or rogue states.

A report by the Government Accountability Office in January said its investigators had found that in many cases the program now was funneling support to scientists working at thriving Russian research institutes including those involved in nuclear programs.

Documents provided Dingell's committee by the GAO, but not in the original report, included "power point" presentations from two leading Russian research institutes involved in the U.S. program that described work also being done for the Iranian nuclear program, the congressmen said.

The committee found that one Russian institute, the Scientific Research Institute of Measuring Systems, received $2.65 million for geologic mapping projects under the US program. The institute also has worked on automated nuclear reactor controls for the Bushehr plant, according to the documents obtained by the House panel.

Another Russian institute, the Federal Scientific and Industrial Center of Nuclear Machine Buildings, received $1 million under the US program for a project involving radioactive medical waste management, the committee said. Dingell said the research institute, which has built a number of Russian reactors, also worked on water circulation pumps and ventilation equipment at Bushehr.

The institute also was to participate in a three-year $1 million joint US-Russia program under the Bush administration's Global Nuclear Energy Partnership to develop pumps for reactors and in several programs involving nuclear waste reprocessing, according to the House committee.

An Energy Department official, who spoke on condition of anonymity because the Russian projects were being reviewed, said the mapping work involved oil and gas exploration and the program under the global partnership was canceled late last year.

The congressmen acknowledged that there was no evidence  that individual scientists, who received assistance from the US program, directly participated in any Iranian nuclear activities.

Still, Dingell said in a statement: "Only this administration, as a result of inattentiveness or incompetence, would send taxpayer dollars to the Iranian nuclear program through a US-Russian program intended to block nuclear proliferation."