Big 12 expansion is dead, according to one of most powerful people in the conference.

Oklahoma athletic director Joe Castiglione told CBS Sports the concept of the league growing beyond 10 teams has ended "for the time being."

"There aren't any signs that we'll talk anymore about expansion for a little while," Castiglione added. "We don't have a timeline on it."

The league announced in June that it would add a conference championship game, starting in 2017, while continuing to discuss expansion. However, it was clear that early June day in Irving, Texas, that expansion was no longer a front-burner issue.

"I think it's fair to say, I think, there were still some questions raised about whether adding members was going to be the right thing or if, in the end, it was going to be dilutive," Big 12 commissioner Bob Bowlsby told reporters.

Big 12 presidents and chancellors will next meet on July 19; expansion is expected to be discussed.

"I don't know where we're at," Bowlsby told CBS Sports on Wednesday. "I know we haven't brought it to a conclusion. That conclusion may very well be status quo. Until we get together and the chancellors and presidents make it a decision, I consider it a pending issue."

Any decision on expansion is expected to be announced as unanimous.

Castiglione is one of two high-placed sources to tell CBS Sports Big 12 expansion is over. The other source, who preferred to remain anonymous, said expansion was dead regarding "those teams."

That's a reference to usual group of schools attached to the Big 12 that includes BYU, UCF, Cincinnati, Colorado State, UConn, Houston and Memphis.

"I stop short of speaking in absolutes about anything regarding conference realignment outside the contracts that exist," Castiglione said. "We've seen things happen that one could never imagine ... [but] I don't see any conversation in the near future."

The conference has researched expansion at least since June 2015 when Oklahoma president David Boren said the league was "psychologically disadvantaged" without more teams, a network and a conference championship game.

The Big 12 dismissed the idea of a "linear network," according to Bowlsby at last month's meetings. Shortly before the championship game announcement, Boren said the league was "in a position of strength."