NFL-Owners, players to open labor talks within month

* Union has warned lockout by owners may occur in 2011

* League owners want to cut player salary costs

* Owners won't open financial books as union wants

By Ben Klayman

CHICAGO, May 16 (Reuters) - The National Football League and its players will open talks in the next month for a new labor agreement in hopes of avoiding a work stoppage in America's most popular sport, officials said on Saturday.

League owners voted unanimously last year to end their agreement with the NFL Players Association two years early in a move to cut salary costs. The existing deal now ends after the 2010 season.

"There isn't a day where I won't pray for labor peace," NFLPA Executive Director DeMaurice Smith said on Saturday at a sports law conference in Chicago.

"This is a game that has grown dramatically because of that labor peace," he added. "But at the same time, our players understand that there may also be a war on the forefront."

Smith was part of a panel that included the heads of the four major U.S. sports' unions, while executives from the management ranks spoke on a separate panel.