Donald Trump claimed to know in advance about the publication on the WikiLeaks website of hacked documents damaging to his opponent Hillary Clinton, according to the Mueller report on Russian interference in the 2016 presidential campaign.

The report by former FBI director Robert Mueller restates the finding by US intelligence that emails stolen from Democratic party organisations and the Clinton campaign chair, John Podesta, had been hacked by Russian military intelligence, the GRU, and provided to WikiLeaks through two online personas, DCLeaks and Guccifer 2.0.

It showed that Trump showed a keen interest in future revelations after WikiLeaks published the first batch of stolen documents in July of that year.

The report quotes Rick Gates, the former deputy chairman of the Trump campaign, as saying that “by the late summer of 2016, the Trump campaign was planning a press strategy, a communications campaign and messaging based on the possible release of Clinton emails by WikiLeaks”.

The relevant section of the report has been heavily redacted by the justice department but one partially retained sentence says: “… while Trump and Gates were driving to LaGuardia Airport, [redacted], shortly after the call candidate Trump told Gates that more releases of damaging information would be coming.”

The report also states: “Within the Trump campaign, aides reacted with enthusiasm to reports of the hacks. Some witnesses said that Trump himself discussed the possibility of upcoming releases.”

It also says Mueller’s office “cannot rule out that stolen documents were transferred to WikiLeaks through intermediaries who visited during the summer of 2016”.

Mueller’s investigation does not say that Trump knew the WikiLeaks publications had been provided by Russian intelligence, but does point to unexplained coincidences and gaps in what the investigators were able to discover.

It notes Trump’s public appeal to Moscow at a rally on 27 July 2016, asking for help in obtaining Clinton’s emails. “Russia, if you’re listening, I hope you’re able to find the 30,000 emails that are missing,” Trump said, in a reference to emails reported to have been stored on a personal server Clinton had used while secretary of state.

The report says: “Within approximately 5 hours of Trump’s statement, GRU officers targeted for the first time Clinton’s personal office.” Mueller’s office found that the GRU sent computer malware hidden in links in emails to 15 accounts in Clinton’s personal office.

“The investigation did not find evidence of earlier GRU attempts to compromise accounts hosted on this domain,” the report says, adding: “It is unclear how the GRU was able to identify these email accounts, which were not public.”

The report confirms direct messages on Twitter exchanged by the president’s son, Donald Jr, and a WikiLeaks account. In one message on 12 October, WikiLeaks thanks him and his father for “talking about our publications”, and encourages them to use a link to their archive of hacked emails which would help Trump in “digging through” the emails. Two days later, the report said, Donald Jr tweeted the link.

In the last month of the campaign, Trump mentioned WikiLeaks 164 times. But asked for his reaction to the arrest last week in London of the group’s founder, Julian Assange, he told reporters: “I know nothing about WikiLeaks. It’s not my thing.”

The report does not say whether Assange was aware that DCLeaks and Guccifer 2.0 were being run by Russian military intelligence. But the report alleges that Assange tried to cover-up the source of the hacked material by hinting it had come from Seth Rich, a former Democratic party staffer who was shot dead in Washington in July 2016.

Right-wing activists in the US have circulated suggestions, with no basis in fact, that Rich was a whistleblower who had been murdered for giving away party secrets.

The Mueller report said it was able to identify “when the GRU (operating through its personas Guccifer 2.0 and DCLeaks) transferred some of the stolen documents to WikiLeaks”, and it publishes communications between Assange and DCLeaks and Guccifer 2.0 offering to coordinate the leak of the hacked documents.

It also confirms the US intelligence view of the extensive scale and reach of the covert Russian effort to skew the 2016 election, a finding that Trump has frequently called into question. “The Russian government interfered in the 2016 presidential election in sweeping and systematic fashion,” the report states.

There was no immediate reaction from the Kremlin to the report, but Russian state TV described the Mueller investigation in terms that echoed Republican talking points: “Two years of work and tens of millions of dollars wasted.”

Leonid Slutsky, the head of the Russian parliament’s foreign affairs committee, said the allegations of Russian meddling in the 2016 elections were “absurd” and part of an “internal political struggle in Washington”.