Shares of telecommunications giant AT&T Inc. and media company Time Warner Inc. fell in premarket trading on Wednesday amid fears that U.S. President-elect Donald Trump will hold good on his vow to block their proposed $85 billion merger.

Trump, who had railed against the media during the fractious presidential election campaign, had said AT&T's proposal to buy the owner of CNN and the Warner Bros movie studio was an example of a "power structure" that was rigged against him and voters.

"It's too much concentration of power in the hands of too few," Trump said during a rally on Oct. 22.

AT&T's shares were down 1.2 percent at $36.55, while Time Warner's were down 3.1 percent at $85.11.

S&P e-mini stock index futures were down 1.8 percent at 7 a.m. ET (1200 GMT) as global markets reacted nervously to Trump's surprise defeat of Democrat Hillary Clinton.

AT&T offered $107.50 per share for Time Warner last month, aiming to acquire content to attract a growing number of online viewers.

AT&T said the Department of Justice would review the deal, which is likely to face intense scrutiny given that lawmakers are already concerned about cable company Comcast Corp's $30 billion acquisition of NBCUniversal.