WASHINGTON (Reuters) - President Donald Trump clamored for the speedy release of emails hacked from Democrats during the 2016 election campaign, and a top Trump aide promoted the idea that Ukraine, rather than Russia, was behind the cyber attack, documents from special counsel Robert Mueller’s probe showed on Saturday.

U.S. President Donald Trump speaks to the media on the South Lawn of the White House in Washington, U.S., before his departure to New York, November 2, 2019. REUTERS/Yuri Gripas

The Justice Department released 500 pages of interview summaries, emails and other documents related to Mueller’s report detailing Russian meddling in the 2016 U.S. election. They were released after a court battle with BuzzFeed News and CNN.

The documents, some of which were posted here Saturday by the online news outlets, include summaries of FBI interviews with Trump's deputy campaign chair Rick Gates, his campaign chairman Paul Manafort, former campaign lawyer Michael Cohen and Steve Bannon, the former presidential adviser.

Gates told investigators on April 10, 2018 that Manafort during the 2016 campaign believed a hack of Democratic National Committee emails was “likely” carried out by Ukrainians, not Russians, the documents showed. A lawyer for Gates did not immediately respond to a request for comment.

Trump’s allies later promoted that theory to undermine Mueller’s conclusions about Russian interference, but it has been discredited.

The House of Representatives current impeachment probe of the president is looking at whether Trump improperly pressured Ukraine President Volodymyr Zelenskiy to investigate his political rival, former Vice President Joe Biden, in a July phone call.

In that call, Trump pressed the Ukrainian president to investigate possible Ukraine involvement in the 2016 election email hacking.

The Gates interview notes also suggested that the Republican National Committee has more knowledge then previously disclosed about the hacked DNC emails.

Gates told investigators the RNC had “non-public information” about the timing of the release of the emails on website WikiLeaks but did not identify who at the RNC knew this information. The RNC has not commented on the documents’ release.

WikiLeaks founder Julian Assange was charged with conspiracy to commit computer intrusion by the U.S. government in April.

He and the website he founded “have effectively acted as an arm of the Russian intelligence services for years,” U.S. Senate Intelligence Committee Chairman Richard Burr, a Republican, said then.

During the campaign, Trump was frustrated that WikiLeaks was slow in releasing DNC emails that the Trump campaign was told WikiLeaks had obtained, the newly released Mueller documents showed.

When Wikileaks did dump a series of documents, Gates said the campaign’s response was “euphoric.”

In July 2017, Trump publicly asked Russia for help finding emails his election rival Hillary Clinton, the former secretary of State, had not made public during a State Department inquiry into her use of a private email server.

Trump later backtracked, telling Fox News saying “Of course I’m being sarcastic.”

“Trump was generally frustrated Clinton’s missing emails had not been found,” Gates said in an interview, the notes show.

The documents also include email correspondence between Bannon and Jared Kushner, Trump’s adviser and son in law, as well as a “proposal to obtain” and analyze emails belonging to Clinton, which was sent to Bannon by conservative activist and former congressional staffer Barbara Ledeen.

BuzzFeed filed a Freedom of Information Act request seeking all documents related to the investigation by former FBI director Mueller and a lawsuit to get access to the documents.