MATTHEWS, N.C. — Family Dollar Stores Inc. on Wednesday delayed a vote by shareholders on the company’s proposed $8.5 billion merger with Dollar Tree Stores Inc. The vote is now scheduled for December 23.

Family Dollar Stores Inc. on Wednesday delayed a vote by shareholders on the company’s proposed $8.5 billion merger with Dollar Tree Stores Inc. The vote is now scheduled for December 23.

Family Dollar is postponing the vote by nearly two weeks as Federal Trade Commission regulators review additional disclosure documents related to the deal.

Family Dollar noted that it expects details on the divestitures regulators will require to sign off on the deal to come during the first week of December.

The special meeting had been scheduled for December 11. Family Dollar stockholders of record as of October 30 can vote on the Dollar Tree deal, worth $74.50 a share, as well as on compensation agreements for certain Family Dollar executives after the merger is completed.

The companies had been aiming to complete the deal by year’s end, although that target could be jeopardized by the decision to postpone the special meeting.

Family Dollar’s board of directors has unanimously endorsed the Dollar Tree offer over a richer, all-cash bid from Dollar General Corp. worth $80 a share.

Family Dollar directors assert that the Dollar General bid is unlikely to win approval from federal antitrust regulators.

Dollar General responded with a pledge to divest up to 1,500 stores to satisfy the FTC, but the offer was unpersuasive to Family Dollar’s board.

So Dollar General launched a hostile bid directly at Family Dollar shareholders. It recently extended its tender offer to December 31 to see what might emerge from the FTC review of the rivals’ merger bid and to allow Family Dollar stockholders more time to opt for the more lucrative bid.