President Trump reacted to the indictment of his former campaign chairman Monday by turning attention to his former political rival, Hillary Clinton.

"Sorry, but this is years ago, before Paul Manafort was part of the Trump campaign," Trump said in a tweet. "But why aren't Crooked Hillary & the Dems the focus?????"

"Also," he continued. "There is NO COLLUSION!"

Manafort's indictment on federal conspiracy charges largely focus on his activities working for the Ukrainian government from 2006 through 2015. Special counsel Robert Mueller unsealed a 12-count indictment Monday alleging conspiracy, money laundering, failing to register as foreign agents, and making false statements to investigators.

More: Former Trump campaign chair Paul Manafort and aide Rick Gates charged with conspiracy, money laundering

More: Paul Manafort and Rick Gates: A timeline of links between Trump's campaign and Russia

The indictment, which also charges Manafort associate Rick Gates, makes no mention of the Trump campaign or even of Trump himself. Mueller, who was appointed special counsel in May, has a wide-ranging mandate to investigate "any links or coordination between the Russian government and the campaign of President Donald Trump," but also other matters that arise from that investigation, including obstruction of justice.

More: Paul Manafort indictment: Read the full document

Trump spent the weekend on Twitter, after news that charges could be made public as soon as Monday, calling the investigation a "witch hunt" and advancing the case for charges against his former rival, focusing on her role in the Obama administration's sale of Uranium to Russia and a lawyer for her campaign who funded a "dossier" of anti-Trump allegations.

He also suggested that the timing of the indictment was an effort to derail his proposal for tax reform.

"I know Mr. Manafort. I haven’t spoken to him in a long time, but I know him," Trump said in August after the FBI raided Manafort's home. "He was with the campaign, as you know, for a very short period of time — relatively short period of time. But I've always known him to be a good man."

A former campaign aide to Donald Trump has pleaded guilty to lying to federal agents working for special counsel Robert Mueller as part of his probe into possible co-ordination between the Trump campaign and Russia.

George Papadopoulos pleaded guilty to one count of lying to FBI agents about the nature of his interactions with "foreign nationals" who he thought had close connections to senior Russian government officials.

He pleaded guilty on October 5, and the plea was unsealed on Monday.

He is the first person to face criminal charges that cite interactions between Trump campaign associates and Russian intermediaries during the 2016 presidential campaign.

Papadopoulos was a member of the campaign's foreign policy team, but Trump aides have said he played a limited role in the campaign and had no access to the candidate.

Court papers revealed that Papadopoulos was told about the Russians possessing "dirt" on Democrat Hillary Clinton in the form of "thousands of emails" on April 26 2016, well before it became public that the Democratic National Committee and Clinton campaign chairman John Podesta's emails had been hacked.

Papadopoulos has been co-operating with investigators, according to court papers, a potentially ominous sign for others in the Trump orbit who might be implicated by his statements.

The White House declined to comment on the details of the Papadopoulos plea, and Mr Trump's Twitter account was also silent on the plea.

The interactions at the centre of the case included speaking with Russian intermediaries who were attempting to line up a meeting between Mr Trump and Russian President Vladimir Putin and offering "dirt" on Mrs Clinton.

The court filings do not provide details on the emails or whom Papadopoulos may have told about the Russian government effort.

The FBI interviewed Papadopoulos about his Russian connections on January 27, a week after Mr Trump's inauguration. The interview predates Mr Mueller's appointment but was part of the FBI probe into Russian election interference that he has taken over.

Papadopoulos was arrested over the summer at Dulles International Airport and has since met government officials "on numerous occasions to provide information and answer questions".

AP

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