U.S. and Russian space agency officials are considering temporarily pulling astronauts off of the International Space Station, The Wall Street Journal reports Monday, following last week's failure of an unmanned cargo mission to the international space station.

No final decisions have been made, a senior official from the National Aeronautics and Space Administration told the Journal, noting that Russian experts are still cautiously optimistic that they can determine and correct the problems that caused the crash within the next two months. But the official said that NASA is currently pursuing backup plans to temporarily abandon the space station if Russian Soyuz rockets are not ready to resume flights by mid-November.

A Soyuz-U rocket which carried an unmanned Progress supply module broke down last week, and the ship ended up crashing in Siberia, the Journal reports. The incident raised questions about the safety of the particular rockets, which use the same motor that carry manned capsules to the space station.

A Russian government panel is expected to release a preliminary report into the matter by late next week, Interfax said.

Three of the crew members who were aboard the station-two Russians and one American-have already pushed back their Sept. 8 return date by at least a week while the probe of the crash continues. In a news conference, Mike Suffredini, the manager of the space station for NASA, signaled that within the next few weeks, the station's crew is likely to be reduced from six astronauts to three.

Suffredini emphasized in the news conference that the current crew is in no immediate danger and we have plenty of options about how to keep the station performing safely with either no crew or a reduced crew.  

If a replacement crew cannot get up to the space station by mid-November, both Russian and U.S. space officials said that the station would likely have to keep operating with astronauts aboard, which has not happened for decades.

Originally, there were plans to launch a new crew to the space station on Sept. 22. However, those plans have been postponed until Russian officials investigate why the rocket failed, USA Today said.  The Journal reports that the launch will likely take place in either October of the beginning of November.