FILE PHOTO: Former Trump campaign manager Paul Manafort arrives for arraignment on a third superseding indictment against him by Special Counsel Robert Mueller on charges of witness tampering, at U.S. District Court in Washington, U.S. June 15, 2018. REUTERS/Jonathan Ernst//File Photo

WASHINGTON (Reuters) - U.S. President Donald Trump’s former campaign chairman Paul Manafort will be sentenced on March 13 for attempted witness tampering and conspiring against the United States, according to a court filing on Monday.

Judge Amy Berman Jackson, the federal judge presiding over Manafort’s case in Washington, had previously tentatively scheduled the sentencing hearing for March 5. She did not give a reason for the delay.

Manafort pleaded guilty last year to conspiracy against the United States and began cooperating with prosecutors working on U.S. Special Counsel Robert Mueller’s probe into Russian meddling in the 2016 presidential election and possible links between the Trump campaign and Moscow.

Both Moscow and Trump deny any wrongdoing.

In November, prosecutors accused Manafort of breaching his plea deal by lying to federal investigators. Lawyers for Manafort have said he was truthful with the investigators.

A closed hearing was held on Monday to hash out whether Manafort violated his plea deal.

In a separate case connected to the Mueller investigation, a jury in Virginia convicted Manafort of bank and tax fraud in August. No sentencing date has been set in that case.