A United States judge has ordered President Donald Trump's indicted campaign advisers Paul Manafort and Richard Gates to remain under house arrest while rejecting their pleas for less stringent bail conditions.

Key points: Judge tells Donald Trump's aides that this is "a criminal trial, not a PR campaign"

Judge tells Donald Trump's aides that this is "a criminal trial, not a PR campaign" Manafort's lawyers argue that his case has been "embellished" by the Russia probe

Manafort's lawyers argue that his case has been "embellished" by the Russia probe A bail hearing is to be held on Monday, prosecutors fear men may flee the country

US District Judge Amy Berman Jackson also sharply warned lawyers for the duo not to speak about their case outside of court.

"This is a criminal trial and not a public relations campaign," Judge Jackson said during a hearing.

"I expect counsel to do their talking in the courtroom and in their pleadings, and not on the courthouse steps."

Mr Manafort, 68, who served as Mr Trump's campaign manager, and Mr Gates, 45, who also worked on the Republican's 2016 campaign, pleaded not guilty on Monday to a 12-count indictment, whose charges included conspiracy to launder money and conspiracy against the US, and failing to register as foreign agents of Ukraine's former pro-Russian Government.

A conviction on conspiracy to launder money alone could carry a sentence of up to 20 years in prison.

In a filing with the court on Thursday, Mr Manafort's attorney Kevin Downing argued that the case brought by special counsel Robert Mueller was "embellished" and that the bail conditions should be softened because Mr Manafort does not pose a flight risk.

Mr Manafort's attorney's defended him as a "successful, international political consultant" who, by nature of his work on behalf of foreign political parties, was necessarily involved in international financial transactions.

Sorry, this video has expired Mr Manafort (R) and associate Rick Gates (L) both pleaded not guilty to the charges. (Photo: AP/Reuters)

Mr Gates' attorneys made a similar requests to the court, describing the business associate as a "devoted husband and a very involved father".

Prosecutors fear men may flee the country

But Judge Jackson said initial bail terms for both men would remain in place for now, and set a bail hearing for Monday to consider changes.

Mr Manafort and Mr Gates are under house arrest, under unsecured bonds of $US10 million ($13 million) and $US5 million ($6.5 million), respectively — prosecutors have argued there is a risk the men would flee.

Mr Mueller's team is probing conclusions reached by top US intelligence agencies and others that Russia interfered in the election to undercut Americans' faith in their democracy, undermine Democratic candidate Hillary Clinton and help Mr Trump.

The inquiry also will determine whether or not there was any coordination between Russians and associates of the Trump campaign.

The Kremlin has repeatedly denied meddling, while Mr Trump has denied collusion between his associates and Russia, calling the investigations a "witch hunt".

Loading...

Reuters