MOSCOW, May 16 (RIA Novosti) - An aide to the Russian president called Tuesday for hydrocarbon resources to be used rationally.

Igor Shuvalov, Russia's representative to the Group of Eight industrialized nations, said Russia's oil output was declining, but rejected suggestions that it sell licenses to all its deposits.

"We should distribute the resources so that they can last for 30 years until we make the transition to alternative energy sources," Shuvalov said.

He also said Russia was planning to develop energy-saving technologies, including the construction of 40 nuclear power units.

Shuvalov said Russia was ready to admit foreign companies to its fuel and energy market but their participation should be limited to volumes needed to develop existing and new capacities.

"In principle, investments also have a limited nature: they should be sufficient to fill the existing capacities, to develop... new capacities and provide our Western partners with the necessary raw materials," he said.

He said Russia was interested in foreign energy processing technologies for its fuel and energy sector but called for a balance of interests in this sphere to be observed.