Baseball umpires reached a tentative agreement on a new contract with the major leagues today and said they would return to work this afternoon.

The umpires had walked out Saturday for the sixth time in 21 years following a breakdown in negotiations for a new agreement. But the sides resumed talks Sunday afternoon at the offices of the National League's law firm and agreed on a deal early this morning.However, because of the lateness of the agreements, the umpires union did not know if regular umpires would be able to reach all sites in time for games. Eight openers were scheduled, including six day games.

The sides began closing in on a deal Friday, but talks broke down shortly before 3 a.m. Saturday over what management negotiator Robert Kheel said was an ultimatum on money from Richie Phillips, head of the the umpires association.

At the time, Phillips said the sides were approximately $750,000 apart, but Kheel said he believed the difference was twice that.

The American and National Leagues had amateur umpires in place to work the final two days of exhibition games. The amateurs also had been assigned to work today's openers.

Phillips had planned to have umpires picket games in Cincinnati, Texas and New York. President Bush is scheduled to go to tonight's game in Texas and the umpires had asked him not to cross their intended picket line.

Under the expired four-year contract, umpires were paid from $41,000 to $105,000 per season, depending on seniority. The leagues said they had offered to increase the minimum to $57,500 and the maximum to $155,000.