Warsaw had held out on approving the deal to examine an adjustment mechanism to keep the cap below the market price. Sados said this mechanism would keep the price cap at least 5% below the market rate.

    The EU can now launch a written procedure to approve the deal, and aims to formally announce it on Sunday, he said.

(Reporting by Jan Strupczewski, writing by Kate Abnett, editing by Geert De Clercq)