MOSCOW (AFP)--Russia said Tuesday it has signed contracts worth $1 billion to supply uranium for U.S. nuclear reactors, the first such deals between the two countries.

Techsnabexport, the export arm of the Russia's Federal Nuclear Energy Agency, or Rosatom, signed the contracts in Moscow with three U.S. companies grouped together in the firm Fuelco, Rosatom spokesman Sergei Novikov told AFP.

The three U.S. companies were named as Luminant, Ameren UE and Pacific Oil and Gas.

"The deal is worth $1 billion and runs from 2014 to 2020," Novikov said.

The agreement on the deliveries followed a deal signed last year by Washington and Moscow which authorized Russian uranium exports to the U.S. civil nuclear power industry.