A US federal judge has revoked bail conditions for former Trump campaign manager Paul Manafort, sending him to jail pending trial after a charge of witness tampering.

US Special Counsel Robert Mueller, who is investigating Russia’s alleged role in the 2016 US election, recently said that Manafort had “conspired to corruptly persuade” two potential witnesses to influence their accounts of his lobbying on behalf of political parties in Ukraine.

Last week, Mueller filed new criminal charges against Manafort as well as Russian citizen and former Manafort operative Konstantin Kilimnik, charging both “with conspiracy to obstruct justice and obstruction of justice.”

On Friday, Mueller's office convinced Judge Amy Berman Jackson to revoke Manafort's $10 million bail, which enabled him to remain on home confinement since he was first indicted last October.

"I cannot turn a blind eye to this," Jackson said in a Washington courtroom, explaining that she could not just release Manafort with more restrictions.

"This isn’t middle school, I can’t take your phone," she added.

After Jackson's ruling, Trump tweeted, "What a tough sentence for Paul Manafort, who has represented Ronald Reagan, Bob Dole and many other top political people and campaigns."

Manafort will remain in pretrial detention until a trial in September. He also faces a separate trial in Virginia set for July.

His charges include conspiracy against the United States, conspiracy to launder money, acting as an unregistered agent of a foreign principal, making false and misleading Foreign Agents Registration Act statements, and false statements.