A formal announcement by the NBA that it will postpone the start of training camp is expected for Friday.

Negotiations on Thursday ended without a labor agreement or even progress toward a new deal, sources said.

The next negotiating session has not been scheduled, but the two sides agreed to contact each other with possible dates to reconvene next week, sources said. 

When a general deal is reached, it is expected to take at least two weeks to write complete terms and finalize smaller details.