US President Donald Trump has played down the importance of an ex-campaign aide indicted in the Russia inquiry.
He said his onetime foreign policy adviser George Papadopoulos was a "low level volunteer" and "liar". Mr Trump once called him an "excellent guy".
Papadopoulos, 30, this month pleaded guilty to lying to the FBI about his Kremlin-related contacts.
Two other ex-aides have been charged as part of the investigation into alleged Russian meddling in the US election.
The other two, former campaign chief Paul Manafort and Rick Gates, appeared in court on Monday to deny charges including money laundering.
In Tuesday morning's tweets, Mr Trump attempted to deflect scrutiny on to the Democratic party, or his tax reform proposals.
He tweeted: "The Fake News is working overtime. As Paul Manaforts [sic] lawyer said, there was 'no collusion' and events mentioned took place long before he came to the campaign.
However, the indictment alleges Mr Manafort and Mr Gates conspired financial crimes from 2006-17, which does include the period over the summer when Mr Manafort served as manager for the Trump campaign.
"Few people knew the young, low level volunteer named George, who has already proven to be a liar. Check the DEMS!" Mr Trump's tweets continued.
Papadopoulos appears in a photo that Mr Trump tweeted of himself in March 2016 hosting a national security meeting with his foreign policy team.
Russians laugh at Washington 'circus'
By Adam Robinson, BBC Monitoring
The main reaction to the allegations of meddling in the US election on Russian state TV is to make fun of it.
"Of course! Vladimir Putin is in charge of everything!" a Rossiya 1 TV presenter on one of the many stage-managed political talks that dominate Russian TV schedules says to audience laughter, as he looks at a CNN graphic linking Paul Manafort to President Vladimir Putin.
The main argument is that there is no evidence that links Moscow to any of this, and that the whole thing is part of an anti-Russian campaign.
The culprits are variously described as Democrats unable to reconcile themselves to Donald Trump's election victory, or unreconstructed Western Cold Warriors worried about a newly assertive Russia.
"Can you imagine how badly Russia has undermined American democracy?" the presenter of another talk show over on Channel One asks viewers sarcastically.
A hard-line pro-Kremlin nationalist on the show thunders that Russia is being punished for standing up to a "neo-colonialist" America.
But another guest looks on the bright side, pointing out that the "circus" in Washington could help strengthen Russia's reputation as a bastion of relative stability and common sense.
In court documents released on Monday, federal investigators said Russian nationals had contacted Mr Papadopoulos to gain influence with the Trump campaign.
They offered "dirt" in the form of "thousands of emails" on Democratic presidential candidate Hillary Clinton in April 2016, according to an indictment.
That was two months before a trove of embarrassing emails related to Mrs Clinton's campaign were leaked after alleged Russian hacking of Democratic accounts.
Papadopoulos, who secretly pleaded guilty weeks ago to lying to the FBI about those contacts, has been co-operating with investigators for months.
The White House said on Tuesday the Trump campaign provided Mr Mueller's team with the Papadopoulos emails.
Press secretary Sarah Huckabee Sanders said on Tuesday: "What Papadopoulos did was lie and that's on him, not on the campaign."
She also told reporters the Mueller inquiry was "an investigation that frankly most Americans don't care too much about".
Ms Sanders added: "We have confidence that it's going to come to a close in short time."
However, there is no sign that a conclusion to Justice Department special counsel Robert Mueller's inquiry is imminent.
Aaron Zelinsky, a prosecutor on Mr Mueller's team, told Papadopoulos' plea hearing this month: "There's a large-scale, ongoing investigation of which this case is a small part."
In Moscow, Russian foreign ministry spokeswoman Maria Zakharova poured scorn on the US in the wake of the indictments.
She referred to "photographs" of Osama Bin Laden meeting White House officials, an apparent reference to a faked photo of Hillary Clinton shaking hands with the late al-Qaeda chief.
Ms Zakharova also pointed out that the Manafort indictment contained an error.
The charge sheet wrongly stated that Julia Tymoshenko, the former Ukrainian prime minister, had served as president.