NBA owners and players are meeting again in what Commissioner David Stern has called "a very important day in these negotiations."

With the league's collective bargaining agreement to expire at the end of the month, Stern is placing added significance on this session after the sides met Friday. He says time is running out but believes both parties are doing the best they can to make a deal before June 30. Without one, owners are expected to lock out the players.

Owners are anticipating a proposal from the players that would address the economic differences that divide them.

The Spurs' Tony Parker and the Hawks' Al Horford are among the stars who joined the union's executive committee for Tuesday's talks.