Derek Carr #4 of the Oakland Raiders throws the ball as he is hit by Andrew Gachkar #59 of the San Diego Chargers at O.co Coliseum on October 12, 2014 in Oakland, California. (credit: Ezra Shaw/Getty Images)

LOS ANGELES (CBSLA.com) — The Chargers and Raiders are moving forward on a back-up plan to share a privately financed $1.7 billion stadium in Carson, according to published reports.

While the teams would continue negotiations to move to new stadiums in San Diego and Oakland, they said in a joint statement posted on the Chargers’ website that they will also work on the proposal to that would see them share a 68,000-seat facility at the 405 Freeway and Del Amo Boulevard.

“We are pursuing this stadium option in Carson for one straightforward reason: If we cannot find a permanent solution in our home markets, we have no alternative but to preserve other options to guarantee the future economic viability of our franchises,” the statement reads.

According to the Los Angeles Times, an official announcement of the plan is slated for Friday at the 168-acre site.

» PHOTOS: Raiders, Chargers Plan Possible Shared L.A. Stadium

The proposal rivals one that St. Louis Rams owner Stan Kroenke and Stockbridge Capital, which owns the former Hollywood Park racetrack, have announced in Inglewood. There, an 80,000-seat NFL stadium would be part of a complex that also includes a theater, retail businesses and a residential district. The city of Inglewood will hold a referendum on the plan later this year.

The Chargers-Raiders plan, meanwhile, centers on a stadium that could be expanded to more than 72,000 seats, according to the Times’ report. It would have parking for 18,000 vehicles.

The two teams are working with a group of business and labor leaders called “Carson2gether,” the Times said. That group plans to begin a petition drive to put a stadium referendum on the ballot or seek approval for the project by the Carson City Council.

The NFL has said it has no plans for any of the three teams to move to Los Angeles in 2015, but the Chargers, Raiders and Rams are all on year-to-year leases at their current facilities. In addition, the NFL has said any team moving to Los Angeles would need approval from three-quarters of the league’s owners.

“Throughout this process we will respect the rules and procedures set forth by the League and defer completely to the ultimate decision of the NFL’s owners,” the Chargers-Raiders statement says.

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