Western Force say the process being used to evaluate the futures of the club and Melbourne Rebels in Super Rugby is "inconsistent and inequitable".
Super Rugby's governing body SANZAAR announced on Sunday the competition is to be cut to 15 teams, with two South African franchises and one Australian side to lose their place.
The Australian Rugby Union (ARU) has since confirmed the Force and the Rebels are the two teams facing the axe and it will be consulting with both clubs.
But, in response, a Force statement read: "The RugbyWA Board had an unsatisfactory meeting with Australian Rugby Union (ARU) management representatives today that highlighted that the terms of the assessment and process being used to evaluate ourselves and the Rebels were inconsistent and inequitable.
"Discussions also failed to address the responsibilities that exist in the Alliance Agreement between RugbyWA and the ARU and we felt in order to protect our position it was necessary to issue legal proceedings to protect our rights under the Alliance Agreement.
"Initially we had particular concerns about the 72-hour deadline to respond, however we have now been advised that we will have further time to present our business case.
"Today [Monday] further highlighted the importance of the Own the Force campaign to strengthen our negotiating position with the Australian Rugby Union to ultimately secure the Road Safety Western Force in Perth.
"We urge all supporters who pledged their commitment to now consider becoming a shareholder of the Western Force Owners Ltd.
"In the meantime, we will work with our partners, staff and Government to develop the best possible business case to take to the ARU."
The Rebels also released a statement, which said: "It's business as usual for the Melbourne Rebels despite this morning's announcement by the ARU.
"While disappointed by the prolonged decision-making process, the club is solely focused on Saturday night's Australian derby against the Brumbies at AAMI Park.
"The club is increasingly frustrated by the impact this process has had on Rebels players, staff, members, fans and partners and the club wishes the management of the issue had been better handled by SANZAAR or the ARU."