NEW YORK - NBA owners and locked-out players met a federal mediator for more than 16 hours before the longest contract negotiating session of the bitter money dispute ended on Wednesday with no public comments.

The first two weeks of the 2011-2012 NBA season have already been wiped out, and NBA commissioner David Stern said more games could be lost if the two sides, widely split on how to divide revenue, could not make progress.

The marathon session was the longest since the lockout began on July 1 and the first to feature US mediator George Cohen, who entered a similar collective bargaining dispute earlier this year with American football owners and players.