WASHINGTON, May 10 (Reuters) - AT&T's $600,000 deal with U.S. President Donald Trump's personal attorney, Michael Cohen, specified that Cohen would advise the company on its $85 billion merger with Time Warner, the Washington Post reported on Thursday, citing company documents.

Trump expressed opposition to the merger during the campaign and his administration ultimately chose to fight it, with the Justice Department filing suit in November to block the agreement. The case has yet to be decided.

The Justice Department wants AT&T to divest Time Warner's DirecTV unit or Turner networks as a condition of approving the acquisition. AT&T has argued that divestitures would destroy some of the consumer value of the merger.

Michael Avenatti, an attorney for porn star Stormy Daniels, revealed earlier this week that Cohen had received payments from a number of companies in 2017 and 2018, including AT&T, the Swiss drugmaker Novartis AG, Korea Aerospace Industries Ltd and Columbus Nova LLC.

Columbus Nova was listed in November 2017 as part of the Renova Group, a conglomerate controlled by Viktor Vekselberg, a businessman with ties to Russian President Vladimir Putin.

On Tuesday, Avenatti claimed that Cohen received $500,000 from billionaire Vekselberg in the months after the 2016 U.S. election. Reuters could not immediately verify the claim and it was not clear how Avenatti would have knowledge of any payment from Vekselberg to Cohen.

AT&T said on Tuesday that it had hired Essential Consultants, a company linked to Cohen, in early 2017 around the time of Trump's inauguration, to advise it on working with the new administration.

On Wednesday, AT&T said it had cooperated fully with Special Counsel Robert Mueller in the Russia probe in November and December.

AT&T declined to comment on Thursday's Post story, and Cohen's attorney, Stephen Ryan, did not immediately respond to requests for comment.

In an email to employees dated May 9 and seen by Reuters on Thursday, AT&T said that in early 2017, "We hired several consultants to help us understand how the president and his administration might approach a wide range of policy issues important to the company, including regulatory reform at the FCC, corporate tax reform and antitrust enforcement."

The Washington Post reported that the internal documents it saw specified that Cohen would provide the company advice on its merger with Time Warner.

It reported that the documents showed the company turned to Cohen three days after Trump was elected, seeking his help on a wide range of issues pending before the federal government.