The White House has said the Trump campaign provided the special counsel investigating ties between it and Russia with emails involving George Papadopoulos, a campaign adviser who has pleaded guilty to lying to FBI agents.
Mr Papadopoulos admitted he lied to the FBI about contacts he had with people who claimed to have ties to top Russian officials.
"I think that Papadopoulos is an example of actually someone doing the wrong thing while the president's campaign did the right thing," White House spokeswoman Sarah Sanders said.
"All of his emails were voluntarily provided to the special counsel by the campaign and that is what led to the process and the place that we're in right now with the campaign fully cooperating and helping with that," she told a news briefing.
Mr Papadopoulos, who joined the Trump presidential campaign in March 2016, lied in January about communicating with those individuals to arrange a meeting between then-Republican presidential candidate Donald Trump and Russian President Vladimir Putin, Special Counsel Robert Mueller said in the documents.
Mr Mueller was appointed to look into alleged Russian meddling in the 2016 US election campaign aimed at swaying the vote in favour of Mr Trump.
The documents said an unidentified campaign official advised Mr Papadopoulos around May 2016 that Mr Trump himself "is not doing these trips", but that "it should be someone low-level in the campaign so as not to send any signal".
While not mentioned in the documents, top Trump campaign advisers, including Mr Trump's eldest son, Donald Trump Jr; his son-in-law, Jared Kushner; and campaign manager Paul Manafort met at Trump Tower in New York in June 2016 with Russians claiming to have derogatory information on Democratic rival Hillary Clinton.
It was not known whether that meeting resulted from Mr Papadopoulos' efforts.
Here's the court filing laying out the #Russia dealings of former Trump campaign FP advisor George Papadopoulous: https://t.co/Y7YtpjVlyM
— Caitriona Perry (@CaitrionaPerry) October 30, 2017
The special counsel said Mr Papadopoulos - a Chicago-based international energy lawyer - lied to FBI agents about when he learned from an unnamed foreign professor that Russia claimed to have "dirt" in the form of "thousands of emails" on Mrs Clinton.
Prosecutors said Mr Papadopoulos told agents he had been in contact with the professor before he joined Mr Trump's campaign.
In fact, they said, Mr Papadopoulos met the professor after joining the campaign.
Ms Sanders played down Mr Papadopoulos' campaign role, saying it was "extremely limited" and that he was a volunteer.
She said: "He asked to do things (and) he was basically pushed back or not responded to in any way. Any actions that he took would have been on his own."
Mr Papadopoulos' lawyers said in a statement it was "in the best interest of our client ... that we refrain from commenting on George's case".
The documents were released just after indictments charging Mr Manafort and business associate Rick Gates with multiple offences, including money laundering, conspiracy against the United States and failing to register as foreign agents.
#MakeAmericaGreatAgain #Trump2016https://t.co/aANxirUJJD pic.twitter.com/VlMynYN3sd
— Donald J. Trump (@realDonaldTrump) April 1, 2016
Who are Paul Manafort and Rick Gates?
Manafort indictment has 'nothing to do' with Trump
The White House has also said that the announcement of the indictment of Mr Manafort and Mr Gates has nothing to do with the US President.
They were both indicted by a federal grand jury on 12 counts, including conspiracy against the United States and money laundering, the federal special counsel's office said.
The charges were the first arising from the investigation by Justice Department special counsel Robert Mueller.
Both Mr Manafort and Mr Gates have appeared at a federal district court in Washington where they pleaded not guilty to charges of conspiracy and money laundering.
At a press conference, Ms Huckabee Sanders said there was nothing in the indictment that indicated collusion between the Trump campaign and Russia.
She also said that it was expected that Mr Mueller's investigation would conclude soon.
Mr Manafort and Mr Gates, a business partner who served as his deputy in the Trump campaign, were charged on Friday in the District of Columbia in an indictment unsealed after the two men surrendered to the FBI, the special counsel said in a statement.
"The indictment contains 12 counts: conspiracy against the United States, conspiracy to launder money, unregistered agent of a foreign principal, false and misleading FARA statements, false statements, and seven counts of failure to file reports of foreign bank and financial accounts," the statement said.
FARA is an acronym for Foreign Agents Registration Act.
The indictment said Mr Manafort and Mr Gates generated tens of millions of dollars of income from work for Ukrainian political parties and leaders and laundered money through US and foreign entities to hide payments between 2006 and at least 2016.
The two concealed their work and revenue as agents of Ukrainian political parties, it said.
Mr Trump responded to the charges on Twitter, saying they predated Mr Manafort's tenure on the presidential campaign, despite the indictment stating the activities continued into 2017.
Sorry, but this is years ago, before Paul Manafort was part of the Trump campaign. But why aren't Crooked Hillary & the Dems the focus?????
— Donald J. Trump (@realDonaldTrump) October 30, 2017
The indictment says Mr Manafort and Mr Gates conspired to defraud the US "from in or about and between 2006 and 2017".
Mr Manafort, 68, served Mr Trump's campaign from June to August 2016 before resigning amid reports that he might have received millions in illegal payments from a pro-Russian political party in Ukraine.
Investigations into Russian links with the Trump campaign, including Mr Mueller's and probes by several congressional panels, have dogged Mr Trump's presidency since the Republican took office in January.
Mr Trump has denied any allegations of collusion with the Russians and called the probes "a witch hunt." The Kremlin also has denied the allegations.
US intelligence agencies concluded earlier this year that Russia interfered in the campaign, including by hacking into and releasing Democratic emails in order to try to embarrass Democratic candidate Hillary Clinton.
Among other things, Mr Mueller has been investigating Mr Manafort’s financial and property dealings and his prior work for that political group, the Party of Regions, which backed former Ukrainian leader Viktor Yanukovich, sources have told Reuters.
Investigators also examined potential money laundering by Mr Manafort and other possible financial crimes, according to the sources.
Mr Gates was a long-time business partner of Mr Manafort and has ties to many of the same Russian and Ukrainian oligarchs.
