Prosecutors claim Manafort was drafting the op-ed as recently as last week, in violation of a federal judge's orders prohibiting him from making public statements, according to the court filings obtained by The Associated Press.
In a filing Monday, lawyers for the special counsel's office wrote Manafort has, as late as November 30, been ghost-writing an op-ed with an unnamed Russian colleague "regarding his political work for Ukraine". "Mr. Manafort's current home confinement to his Alexandria residence - set during his initial appearance in this case - was viewed as a short-term interim step by the parties as they continued to work out agreed-upon conditions of release to recommend to the Court".
Manafort, who is facing multiple felony charges for financial crimes related to his lobbying work in Ukraine, has been placed under house arrest while his legal team works out a bond agreement federal prosecutors.
"Immediate family members are therefore personally responsible for substantial payments to the Court should Mr. Manafort not appear as required and should the fair market value of the pledged properties fall below what has been documented", the court filing said.
That writing violated a November 8 court order "prohibiting such out-of-court statements in order to protect the fairness of the upcoming trial", the court filing said. The bail agreement the lawyers appeared to have reached would have freed him from house arrest and Global Positioning System monitoring while asking him to post more than $11 million in real estate as collateral.
The op-ed was being drafted as late as last week, with Mr Manafort now under house arrest. He was working on the draft "with a long-time Russian colleague of Manafort's, who is now based in Russia and assessed to have ties to a Russian intelligence service", according to the special counsel's office.
The government's filing on Monday says that prosecutors learned about Manafort's alleged ghostwriting efforts late last week. Prosecutors did not name Manfort's Kremlin connected colleague, but did note he is now in Russian Federation.
Manafort was indicted in October and charged with conspiracy against the United States, conspiracy to launder money, failing to properly file his foreign-made finances, acting as an unregistered foreign agent and making false statements.