New York (CNN) -- The NBA is giving the players' association until Wednesday to accept a deal over a new collective bargaining agreement after the two sides met for eight hours over the weekend.
The Saturday meeting was the first in eight days for the NBA and the National Basketball Players' Association after discussions broke off last month.
NBA Commissioner David Stern said the new proposal gives players between 49% and 51% of revenues. But the players' association rejected it, he said.
"I think it's fair to say that, speaking on behalf of the union, (players' association lawyer Jeffrey) Kessler rejected the mediator's recommendations and our proposal," Stern told reporters early Sunday morning. "But hope springs eternal and we would love to see the union accept the proposal which is now on the table."
If the players' association does not change its mind by Wednesday, the NBA will offer up another proposal -- one that offers players 47% of basketball revenues.
"We hope that this juxtaposition will cause the union to recess its position and accept the deal," Stern said.
Derek Fisher, the president of the players' association, said he would not take the proposal to the players for a vote.
"We've been given the ultimatum and our answer is, 'That's not acceptable to us," he said.
The proposal says that if the league exceeds certain revenue forecasts, the players would receive 51%. If it didn't, the share would fall to 49%.
"There'd be no way in the world we'd ever get to 51%," Fisher said.
Both sides do not have any more talks scheduled. The season has been canceled through at least November 30, and the two sides are hoping they can reach a resolution before more games are called off.
Stern has said the 2010-2011 season was not profitable for most of the league's 30 owners, who want cost-cutting help from players. The league lost as much as $300 million last season, according to Stern.
One of the battles has focused on the owners' rejection of calls by the players' union for an average $7 million player salary in the sixth year of a new labor deal. The current average salary is about $5 million.
Other big issues include a fight over a move by owners to gain the bigger share of revenues and whether the NBA will strengthen its salary cap.
The league's owners began a lockout of players in early July.