The request was made in a letter to Congress, Griffin told a congressional committee on Tuesday.

The Iran Nonproliferation Act prohibits NASA from buying space-related services and goods from Russia as long as Moscow sells weapons and missile technology to Tehran.

The National Aeronautics and Space Administration will need to use Russian space services starting April 2006 but would not be able to pay for them under the act, Griffin told the House of Representatives' Science Committee.

NASA will need Russia's help to use the International Space Station, he said.

"For the next several years, as the space station development and its partnership go forward, the United States is in the position where we cannot effectively utilize the space station without our Russian partners," Griffin said.

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