The Justice Department has called an 11 am ET press conference on Friday, with antitrust chief Makan Delrahim set to "announce a significant merger enforcement action." The agency has reportedly been pushing Sprint and T-Mobile to divest enough assets to create a viable fourth national wireless carrier in order to secure approval for the $26 billion merger.

Why it matters: According to the Wall Street Journal, The DOJ has also been working to convince a number of state attorneys general, who have sued to block the deal, to approve the transaction with the new conditions.

Sprint and T-Mobile have been talking with Dish Network about selling some spectrum and prepaid business, though analysts have questioned just how viable a national player Dish would make.

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