SEATTLE — BNSF Railway and five environmental groups want to intervene on opposing sides of a federal lawsuit brought by developers of a coal-export terminal against Washington state.

Utah-based Lighthouse Resources, which operates coal mines in Montana and Wyoming, sued Washington officials in November, alleging state officials violated federal laws in denying permits for its Millennium Bulk Terminals-Longview project.

Environmental groups that opposed the terminal filed a motion Tuesday seeking to intervene on behalf of the state.

BNSF Railway separately asked Tuesday to let it intervene as a plaintiff. They say state officials have burdened interstate commerce by blocking the project.

The terminal aimed to move up to 44 million tons of coal by train through a terminal in Longview, Washington, for export to Asia.

The state last fall denied the project a key water permit.

Lawyers for the state have asked the federal judge to dismiss many of the claims and abstain on others.