WASHINGTON (Reuters) - A senior adviser to Donald Trump during his 2016 presidential campaign said Ukraine, not Russia, was responsible for a cyber-breach targeting the Democratic Party, Justice Department documents showed on Saturday.

The new information reveals that President Trump's campaign has tried to get this "harmful information" to his Democratic rival Hillary Clinton and benefit from it.

According to testimony given by the former Trump campaign assistant director Rick Gates to the FBI, then campaign manager Paul Manafort was telling his aides that the hacking of the Democratic Party's email was "probably the work of the Ukrainians, not the Russians," and that these officials said they were convinced that Kiev It was arranged in such a way that the charge could be brought against Russia.

The documents, published by several US media, were brief excerpts of interviews conducted as part of former Special Adviser Robert Mueller's investigation into Russian intervention in the 2016 presidential campaign and included Gates, as well as Trump's former attorney Michael Cohen, and former adviser Stephen Bannon.

The documents show that Gates told the FBI that Trump's former adviser, Michael Flynn, was insisting that the Russians were not responsible for piracy.

Flynn, who briefly served as Trump's first national security adviser, pleaded guilty in 2017 to being guilty of lying to the FBI over his contacts with the Russian ambassador.

The new information shows how the figures surrounding Trump were defending the unfounded theory of Ukraine's role in meddling in the 2016 presidential election, in an attempt to distort Muller's report and divert attention to another direction.

Trump had tried to get the Ukrainians to open an investigation into whether their country intervened in the election.

The excerpts indicate that Gates told the FBI that there were various observations that led him to believe that Trump and his associates learned about WikiLeaks' plans early on.

In July 2016, Wikileaks began posting thousands of Democratic Party emails, and US intelligence later said the emails were obtained through Ross's spies and were then sent to Wikileaks.

Documents released on Saturday also show that Trump, his top advisers and members of his family have repeatedly discussed how to seize those emails.

Efforts to isolate Trump entered a new phase last Thursday with the House vote on a decisive measure that will open a new stage in the investigation of the "Ukrainian scandal", authorizing the questioning of witnesses in public hearings, a move described by the President in tweets on Twitter as "the largest political chase campaign in history American".

The leadership of the Democratic Party decided on September 24 to follow the path of "isolation mechanism", after disclosing information about Trump's telephone conversation with Ukrainian President Volodymyr Zelinsky last summer in which he asked him to investigate his Democratic opponent Joe Biden and the work of his son Hunter in Ukraine.