The report was handed in moments ago, adding it was submitted to Attorney General William Barr. Details of the report and its outcome are not yet known. President Trump has denied any involvement with Moscow.
The report was not immediately made public – Mr Barr will have to decide how much to disclose – and it was not known if Mr Mueller found criminal conduct by Mr Trump or his campaign, beyond the charges already brought against several aides.
Mr Mueller, a former FBI director, had been examining since 2017 whether President Trump’s campaign conspired with Moscow to try to influence the election and whether the Republican president later unlawfully tried to obstruct his investigation.
Investigators appeared to be particularly interested in a lucrative business deal with Moscow that was cancelled around the time of his 2016 campaign to become President.
The project came about despite Mr Trump denying any links to Moscow, or Vladimir Putin.
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