The move came after the company agreed not to terminate the pilots' pension plan before February even if it files for bankruptcy.

The tentative agreement must be ratified by the 7,500 active Delta pilots, including more than 800 who are based at the Cincinnati/Northern Kentucky International Airport. The nation's third-largest airline has warned that it would have to file for bankruptcy if did not stem a wave of early pilot retirements by the end of September.

But the agreement still does not resolve Delta's larger problem: getting the pilots to agree to $1 billion in concessions. The Atlanta-based airline has also warned of the possibility of a Chapter 11 filing without the concessions.

Delta fears that its pilots could jump ship en masse because they are worried about their pensions amid United Airlines' threat to terminate its employee retirement plans. Several hundred Delta pilots have retired early in recent months, chief executive Gerald Grinstein has said.

Grinstein feared that Delta would not have enough pilots to fly certain types of aircraft - particularly the planes the airline uses on its lucrative international flights.

"Delta is pleased that a tentative agreement was reached, spokesman John Kennedy said.

Delta pilots who retire can elect to receive 50 percent of their pension benefit in a lump sum and the other 50 percent as an annuity later, regulatory filings show.

According to Monday's tentative agreement, the agreement would cover pilots whose retirement date is Oct. 1 or later.

The pilots union said there will be a "random selection process" for those in the post-retirement pool, which can be tapped only when staffing falls below a certain level.