NEW YORK  -- The NFL and its on-field referees union failed to reach an agreement when they met Saturday, and the league said it's proceeding with replacement officials.

The NFL locked out the referees in early June, then hired replacements, whose work in exhibition games has been heavily criticized.

"We met with the NFL this morning and discussed various potential solutions to reach a new collective bargaining agreement," Michael Arnold, lead negotiator for the NFL Referees Association, said in a statement. "Unfortunately, we were unable to reach any agreement.

"We are disappointed because it means that our members will not be back on the field for Week 1 of the regular season due to the NFL's continuing lockout. We remain willing to negotiate with the NFL in order to reach a fair agreement."

Commissioner Roger Goodell was among the league officials involved in Saturday's session.

"Commissioner Goodell and other NFL staff members concluded three days of talks today with representatives of the NFLRA without reaching an agreement," NFL spokesman Greg Aiello said. "No further talks are scheduled. We are proceeding with the replacement officials."

In 2001, the NFL used replacements for the first week of the regular season before a contract was finalized. The speed of the game and the amount of time starters are on the field increase exponentially for real games, making the replacements' task more challenging.

Ray Anderson, the NFL's executive vice president of football operations, told the clubs in a memo Wednesday that the replacements will work "as much of the regular season as necessary," adding that training with each crew will continue.

But the NFL has seen and heard the problems the replacements have had this summer, something that tests the integrity of the sport.

The league and the NFL Players Association began meeting to end their lockout last year in a similar fashion after a lengthy stalemate. But the league and players weren't up against as tight a deadline as the NFL is with the officials.

Among the NFL's proposal is hiring full-time seven officials - one per position of referee, umpire, line judge, side judge, back judge, field judge, head linesman - who would train, scout, handle communications, safety issues and rules interpretations year-round.

Now, all NFL game officials are part-time employees, with outside jobs ranging from lawyers to teachers to business owners.

In response, the NFLRA has said it is not opposed to full-time officials "if they are fairly compensated."