(AP) The Big Ten and Pac-12 announced Friday that they were scrapping plans to schedule games against each other in all sports, with Pac-12 officials saying there were too many complications with football schedules to pull it off.

The leagues had agreed to the partnership in December, well before a four-team football playoff set to begin in 2014 was approved by a committee of university presidents last month.

Big Ten Commissioner Jim Delany said the league recently learned from Pac-12 Commissioner Larry Scott that coordinating a non-conference football schedule for 24 teams across two leagues by 2017 proved to be too difficult. Delany said those complications included the Pac-12's nine-game conference schedule and previous non-conference commitments.

The Big Ten has previously discussed moving from eight to nine league games and could move in that direction now that league teams aren't playing a Pac-12 opponent every year.

"A great effort was made by both conference staffs to create football schedules that would address the variety of complexities, but in the end, we were just not able to do so," Delany said. "While everyone at the Big Ten is disappointed by the news, we look forward to continuing the historic partnership that we have with the Pac-12 and to working together on other matters in the future."

Scott said the Pac-12 wants to keep playing nine league games while maintaining as much flexibility in out-of-conference scheduling as possible. He said the leagues will continue a close relationship, which includes their long-standing partnership with the Rose Bowl.

"After extensive deliberation and consultation with member institutions, television partners and others, the Pac-12 and Big Ten have decided not to pursue the previously announced plans for enhanced scheduling collaboration across all sports," Scott said.

Pac-12 newcomer Utah recently announced a home-and-home series with Michigan and that its longtime rivalry with BYU would be suspended for those two years, 2014 and 2015, because of the high-profile games with the Wolverines.

"With our intensely competitive nine-game conference schedule, this will allow us to maintain flexibility in our non-conference scheduling. We look forward to continuing our historic partnership with the Big Ten in the future, including our scheduled football home-and-home series with Michigan," Utah athletic director Chris Hill said.

Colorado athletic director Mike Bohn remained hopeful that a mutually beneficial collaboration of some kind is still possible between the Pac-12 and the Big Ten.

"It would be terrific. It's a wonderful vision. I'm disappointed we haven't been able to pull it together," Bohn said.