"Because the defendant's post-trial motions have not been filed or ruled on, the government does not at this time have sufficient information to make an informed decision on whether it will seek retrial of the remaining counts," Mueller's team said in a court filing.

Manafort was convicted of eight other tax crimes and bank fraud charges in that case in U.S. District Court in Alexandria, Virgina.

Special counsel Robert Mueller on Wednesday asked a federal judge for more time to decide whether to seek a retrial for former Trump campaign boss Paul Manafort on 10 criminal charges that jurors were unable to reach a verdict on last week.

"The government, accordingly, respectfully requests that the Court extend the deadline for the government to file notice about the ten remaining counts to one week after the Court has ruled on defendant's post-trial motions," the filing said.

Manafort's lawyers did not object to Mueller's request to extend the deadline.

"The United States has consulted with counsel for the defendant and they do not object the government's motion," Mueller's team wrote.

Jurors reportedly deadlocked by a vote of 11-1 in favor of conviction, on the 10 charges that the 69-year-old Manafort faces in Virginia.

Mueller's request comes less than three weeks before Manafort's next trial, on charges of money laundering, witness tampering and failing to register as a foreign agent, is set to begin in U.S. District Court in Washington, D.C.

That case is also being prosecuted by Mueller's team, and like the Virginia case is connected to work Manafort did for a pro-Russia political party in Ukraine. That work predated his tenure as presidential campaign chairman for Donald Trump for several months in 2016.

Patrick Cotter, a former New York federal prosecutor, told CNBC that there is "absolutely no legal reason" to retry Manafort in Virginia.

"He's facing more than sufficient time under the counts he's been convicted of" without even factoring in the upcoming Washington trial, Cotter said.

But, Cotter added, there's a chance prosecutors will still seek a retrial.

"It wouldn't shock me," Cotter said. "Any lawyer likes to keep their options open as long as possible."