NASA has opened negotiations to purchase more Russian hardware for the international space station in a bid to give that country enough cash to keep up its end of the partnership.

NASA hopes to begin assembly of the new orbital laboratory on Nov. 20., the date it established late last May. But Russia, suffering from an eroding economy, recently announced a new three-month delay in completion of a crucial early component called the service module.Denied most of its budget this year, the Russian Space Agency needs the equivalent of $10 million to complete the service module, said Joseph Rothenberg, NASA's associate administrator for space flight.

Lack of funding has forced the Russians to set back the launch of the service module from April to July 1999. The 42,000-pound module is required to house the new station's first occupants as well as to keep the spacecraft circling at a safe altitude above the Earth.

In an effort to assure funding and stop further delays of the service module, NASA is negotiating for the purchase of two Russian Soyuz crew capsules. The three-person Soyuz craft would be docked to the new station in late 2002 to serve as life boats. The capsules would allow the station's permanent population to grow from three to six astronauts and cosmonauts.

Eventually, the station's resident crew will grow to seven as NASA replaces the Soyuz rescue craft with at least one seven-person U.S. rescue ship that is permanently docked to the station.

"Hopefully, that will give the up front cash to the Russians and they will be able to pay off (their contractors for) the remaining parts they need to get the service module on track," Rothenberg said from Washington.

He could not provide a cost estimate. The trade publication Space News, however, citing Russian space officials, placed the cost of a Soyuz capsule at about $100 million.

According to Rothenberg, the service module lacks 10 relatively small components for completion.

Among the most vital of those are two of three star trackers, optical devices that are needed for the guidance system to keep the station correctly oriented in space.

"These are launch critical," said Rothenberg.