KEY BISCAYNE, Fla. -- Mountain West commissioner Craig Thompson said Tuesday he expects to have a decision on whether San Diego State will remain in the conference by the end of the month.

San Diego State is scheduled to join the Big East on July 1, but the Aztecs are reconsidering after Boise State opted not to join the Big East and remain in the Mountain West.

While the Aztecs must be provided the "right of first option" to join before other schools, the league presidents must vote by a three-quarters majority to approve San Diego State's return to the league, Thompson said.

Thompson said he has been in daily contact with San Diego State athletic director Jim Sterk.

"They want to know how [the Mountain West's] TV deal works," Thompson said. "We want to know their wants, needs and desires."

As part of Boise State's contract to remain in the Mountain West, details of which were obtained by ESPN, MWC presidents must set the terms of SDSU's return and present an offer to the school before moving on to other schools. The "right of first option" in the contract lasts until Jan. 31, after which time the conference can attempt to invite other schools or stand pat with its current membership.

Sources said the MWC also covets independent BYU, but that it's "unlikely" the Cougars would return to the league.

Big East commissioner Mike Aresco also said he expects a decision fairly soon from San Diego State. If the Aztecs remain in the Mountain West, the Big East will have 10 members in 2013.

Whether the Big East has 10 or 11 members (if San Diego State still joins), the league would only play eight conference football games in 2013, Aresco said. The league schedule will be redone for 2013 once San Diego State's status for 2013 is known.

Aresco said it was "unlikely at this point" that the Big East would have East Carolina and/or Tulane, both scheduled to join in 2014, move in a year early.

On Monday, ESPN's Andy Katz reported that the Big East was considering adding Tulsa and Massachusetts. Aresco would not comment on potential new members.

Aresco said ultimately his league's goal is for 12 teams.

The Mountain West, meanwhile, will have 11 members in 2013 -- 12 if San Diego State remains. Thompson said the league's "No. 1 objective" is resolving whether they will have 12 members.

Thompson said he "doesn't think" the Mountain West would expand to 14 members.