The United States is concerned about the growing influence of security services in Russia, which has complicated co-operative programs designed to keep nuclear materials from extremists, a senior US official said on Tuesday.
Linton Brooks, under-secretary of energy for national security, said legal liability issues over possible accidents have also interfered with US programs to secure and eliminate Russia's vast store of Cold War nuclear materials.
But at a briefing for reporters, Brooks, who also heads the National Nuclear Security Administration, said his agency was working around the roadblocks with Russia as it accelerated post-September 11, 2001, efforts there and elsewhere to guard against nuclear "terrorism."
The Department of Energy's National Nuclear Security Administration was created three years ago to reduce threats to US national security by closing or redesigning foreign plants making nuclear bomb fuel and improving security at decrepit and porous nuclear facilities, among other steps.
Much of the non-proliferation work involves Russia, which along with the United States is the major source of the fissile material that is the fuel for nuclear bombs.
While Washington has worked with Moscow on the nuclear issue since the collapse of the Soviet Union in the mid-1980s, Brooks said access to Russian sites remains a problem.
"There is no secret that many of us in the United States are worried by what we see is the growing influence of security services in the Russian Federation," he said.
Conservative by nature, these services create "pressures ... to give greater emphasis to denying access in the name of security than to facilitating access in the name of co-operation," he said.
While this is a "real problem ... we are finding creative ways to meet Russian concerns," he said.
Neither the United States nor Russia enrich uranium for nuclear weapons fuel and the United States has not made plutonium, the other key nuclear fuel, for decades.
But Russia does make plutonium for three reactors in central Siberia that provide heat and light for the region.
Washington is working to replace these facilities with fossil fuel plants. Brooks said two of the plutonium reactors will be closed in 2008 and the third by 2011.