A former adviser to US President Donald Trump, whose contacts with Russians set off the investigation into possible collusion with Moscow, has been jailed for lying to the FBI.
US District Judge Randolph Moss sentenced foreign policy aide George Papadopoulos to 14 days in prison, noting that he "lied in an investigation that was important to national security".
"In January 2017, I made a terrible mistake for which I paid dearly, I am ashamed," Papadopoulos had told the court in Washington.
"I was young and ambitious."
The judge said he took into consideration Papadopoulos's "genuine remorse" in issuing the light sentence, which included a $9,500 fine, a year on parole and community service.
By lying to investigators, Papadopoulos had made "a calculated exercise of self-interest over the national interest," said Judge Moss.
Papadopoulos has cooperated for more than a year with Special Counsel Robert Mueller's probe into Russian interference in the US presidential election and possible collusion with the Trump campaign.
He has testified that senior members of the Trump campaign encouraged him during 2016 to build ties with Russia, including after he told them that Moscow possessed - and could be willing to share - information on Mr Trump's election rival Hillary Clinton.
Those issues are now at the heart of Mr Mueller's investigation.
Out of the 35 people and entities so far charged, Papadopoulos is one of five who have pleaded guilty and will be the second to be sentenced.
Mr Trump has regularly lashed out against the investigation he dubs a "witch hunt" driven by his Democratic rivals.
Papdopoulos's lawyer Tom Breen said: "The president of the United States hindered this investigation more than George Papadopoulos ever did."
The White House distanced itself from Papadopoulos, referring to his campaign role as nothing more than a low-level coffee boy, after his guilty plea.
The sentence that Papadopoulos received is about half the prison time given to Alex van der Zwaan, a lawyer who was also charged with lying to the FBI during the special counsel's probe.
Van der Zwaan was sentenced to 30 days in prison.
Judge Moss said he wanted to impose some prison time because while he did not "remotely believe Mr Papadopoulos was seeking to assist the Russian government," he was nevertheless troubled by Papadopoulos' selfish motives to lie to the FBI so that he would not lose a shot at getting a possible job in the Trump administration.
