JEFFERSON CITY, Mo. (AP) - Missouri utility regulators have approved the acquisition of a large wind energy project by a Chicago firm.

The decision Wednesday by the state Public Service Commission was a necessary step for Invenergy to buy the rights to construct the proposed Grain Belt Express power line.

The project initiated by Houston-based Clean Line Energy Partners would carry Kansas wind energy on a 780-mile path across Missouri and Illinois before hooking into an electric grid in Indiana that serves eastern states.

Missouri regulators earlier this year reversed their previous denials and gave the green light to the project. Missouri legislators then tried but failed to prohibit eminent domain for the project.

But the project still needs regulatory approval in Illinois, where an appeals court last year overturned the state's previous approval. Invenergy's acquisition also needs approval in Kansas.