Russia used Republican political operative Paul Manafort and the WikiLeaks website to try to help now-US President Donald Trump win the 2016 election, a Republican-led Senate committee says in its final review of the subject.

WikiLeaks played a key role in Russia’s effort to assist Republican Trump’s campaign against Democrat Hillary Clinton and likely knew it was helping Russian intelligence, says the 966-page report, which is likely to be the most definitive public account of the 2016 election controversy.

The report found President Vladimir Putin personally directed the Russian efforts to hack computer networks and accounts affiliated with the Democratic Party and leak information damaging to Clinton.

The Senate select committee on intelligence alleged Manafort collaborated with Russians, including oligarch Oleg Deripaska and “Russian intelligence officer” Konstantin Kilimnik, before, during, and after the election.

The panel found Manafort’s role and proximity to Trump created opportunities for Russian intelligence, saying his “high-level access and willingness to share information with individuals closely affiliated with the Russian intelligence services… represented a grave counterintelligence threat”.

A lawyer for Manafort, who was later jailed for financial fraud crimes, did not respond to a request for comment. Wikileaks did not immediately reply to a request for comment.

It was not clear what effect, if any, the report might have on the current presidential campaign. Trump faces Democrat Joe Biden in the November 3 US election.

Russia’s alleged election interference, which Moscow denies, sparked a two-year-long US investigation headed by special counsel Robert Mueller.

In a report released last year, Mueller found no conclusive evidence of co-ordination between Russia and the Trump campaign. He cited 10 instances in which Trump may have tried to impede his probe but did not say if this constituted obstruction of justice.

Trump and his supporters have consistently bristled at suggestions foreign interference helped his upset 2016 victory. They have sought to discredit the intelligence agencies’ findings as the politically charged work of a “deep state”.

A Trump campaign spokesman said the report vindicated his stance that there was no “collusion” between Trump’s 2016 campaign.

The Biden campaign said Trump had welcomed Russian assistance “with open arms” in 2016.

Founded by Julian Assange, WikiLeaks published thousands of emails hacked from Clinton’s campaign and a top campaign aide in the weeks before the 2016 election, yielding a drum beat of negative coverage about the Democrat.

As Russian military intelligence and WikiLeaks released the hacked documents, the report says Trump’s campaign sought advance notice, devised messaging strategies to amplify them “and encouraged further theft of information and… leaks”.

The report says Trump’s campaign tried to get advance information about WikiLeaks’ planned releases from his adviser Roger Stone but the committee could not establish the extent to which Stone had inside access to WikiLeaks materials.

Stone, who was jailed on charged including lying to investigators and witness tampering, had his 40-month jail sentence commuted by Trump in July.