By Richard Galpin
BBC News, Murmansk
Britain's Prince Michael of Kent has opened a new nuclear storage site in northern Russia funded by the UK.
Murmansk port is home to Russia's nuclear fleet
The Murmansk region in the Arctic Circle hosts Russia's nuclear submarine fleet and nuclear ice breakers.
It has the largest concentration of radioactive waste in the world, much of which is not properly protected.
The British government has provided more than $40m (£21.4m) to enable the hi-tech secure storage site to be built at Murmansk port.
It is all part of a massive international effort to prevent the vast amount of nuclear material scattered across Russia and the other former Soviet republics from either falling into the wrong hands or causing an environmental catastrophe.
Prince Michael cut the ribbon inside the cold, tomb-like building with its huge, heavy steel doors.
Building number five, as it is known, will be used to store spent nuclear fuel from the fleet of icebreakers based in Murmansk.
For the past 20 years the spent fuel, which is highly enriched uranium, has been kept on board several container ships.
One of those ships, despite holding tonnes of enriched uranium, is still sailing around the region picking up yet more spent fuel from nuclear submarines.
A Russian official has admitted there is a high risk of an accident.
Prince Michael said that was why the new storage facility was so important and he stressed this was only the beginning of a major British contribution towards tackling the nuclear problems in the former Soviet Union.
"We hope to produce up to $750m (£400m) in the course of the next 10 years in Russia... to help with this kind of cleaning up of nuclear waste and the environment in general," he said.
Much of that money will be spent at a big former navy base north of Murmansk where large quantities of spent nuclear fuel from submarines and other vessels have been dumped.