The lobby group for some of the most powerful US tech firms said it would join the legal challenge to the planned rollback of "net neutrality" rules requiring internet service providers to treat all online traffic equally.
The Internet Association — a group which includes Google, Facebook, Amazon and Microsoft, among others — announced it would support legal efforts to block the rollback voted last month by the Federal Communications Commission.
The association gave no specifics but suggested it would seek to intervene in lawsuits expected by several attorneys general, including from Washington and New York states.
Internet Association president Michael Beckerman said the FCC action voted December 14 "defies the will of a bipartisan majority of Americans and fails to preserve a free and open internet."
He said the association "intends to act as an intervenor in judicial action against this order and, along with our member companies, will continue our push to restore strong, enforceable net neutrality protections through a legislative solution."
Last month's vote capped a heated partisan debate and is just the latest twist in a battle over more than a decade on rules governing internet service providers.
FCC chairman Ajit Pai, who pushed the latest effort, has argued that the neutrality rule enacted in 2015 served to stifle investment and innovation in a fast-evolving sector.
But net neutrality backers have argued that clear rules are needed to prevent internet service providers from blocking or throttling services or websites for competitive reasons, and that the rollback would increase the power of a few dominant providers to control what users see online.
Lawsuits could not be filed until the FCC's order was published, which occurred this week. Some lawmakers have also begun efforts to invalidate the FCC's action.
The battle over net neutrality has raged for over a decade in the FCC and the courts, with both sides contending they represent "internet freedom."
The 2015 net neutrality rules were backed by then- president Barack Obama and endorsed by a 3-2 Democratic majority at the time. But the election of President Donald Trump reversed the FCC party majority and it quickly reversed course.