The Justice Department has decided to let AT&T close its acquisition of Time Warner, giving up its option to delay the merger for a designated waiting period. But it can still appeal a judge's decision on Tuesday allowing the merger to proceed without conditions even after the transaction is completed.  

"The Department will not be seeking a stay, but continues to evaluate its options with respect to appeal," said a DOJ official. 

Court filings revealed the department's decision, CNBC reported. 

On Tuesday a Federal judge cleared the way for the $85-billion acquisition in a sharp rebuke to the Justice Department, which had opposed the deal. In the wake of the decision, Assistant Attorney General for the DOJ's Antitrust Division Makan Delrahim initially indicated that it would review the judge's opinion and consider its next steps. 

Shares of AT&T (T) - Get Report rose 30 cents, or 0.93% to close at $32.52 Thursday, and was flat in after-hours trading. Time Warner (TWX) rose $1.84 to $100.61 in after-hours action after having gained 90 cents, or 0.92%, in regular session trading.

-David Hatch contributed to this report