During meetings in Moscow on Friday, RKK Energia officials assured NASA that the company would be able to supply one Soyuz piloted spacecraft and two robotic Progress cargo ships for International Space Station (ISS) operations this year.

"We promised to have one Soyuz and one Progress spacecraft ready, by the time Zvezda is launched in July," Grigoriev said.

NASA had previously expressed concern that the Russian decision to continue Mir operations would impair RKK Energia's ability to supply the spacecraft for the ISS.

This would pose a problem if automatic docking operations between the ISS and Zvezda fail, since the plan calls for the Soyuz spacecraft to be in standby mode, ready to carry an emergency crew into orbit to manually complete the docking.

If docking is successful, Soyuz will remain on the ground until October, when it will be used to deliver the first long-term expedition to the ISS.

Meanwhile, a Progress cargo spacecraft may be launched to the ISS soon after it is linked with Zvezda to provide extra fuel for the station.

NASA also requested a third Progress spacecraft for the ISS, for which RKK Energia currently lacks funds. A total of about a dozen spacecraft are currently in different stages of assembly in RKK Energia shops. However, the company has struggled to obtain government funds to keep up the pace of production.