Belykh said that he would take a two-week vacation and then decide on his future plans.
"I can say for sure that I am not going to join another party. Maybe I will get involved in public and political activities," he said.
Gozman, a leading official in the party, said that the SPS would gather for a session on October 2 to decide on its future direction.
The SPS, which advocates a free market economy, performed well in the 1999 parliamentary elections, but gained less than 1% of the vote at the December 2, 2007 polls.