Kelner said Flynn is eager to proceed to sentence as soon as possible, The Washington Post reported on Tuesday after the procedural hearing in the US District Court for the District of Columbia took place.
The report noted that the hearing did not clarify when the case against Flynn will conclude.
In December, Flynn pleaded guilty of lying to the FBI about his contacts with former Russian Ambassador to the United States Sergey Kislyak during the transition period when President Donald Trump assumed power.
Flynn remains a key figure in the investigation into allegations of the Trump campaign collusion with Russia during the 2016 US presidential election.
The retired general said in his plea that during conversations with Kislyak, the two men discussed sanctions on Russia and a United Nations resolution on Israel.
Russia and Trump have repeatedly denied colluding. Moscow has said the allegations are groundless and invented to deflect public opinion from actual instances of US election fraud and corruption as well as other pressing issues. Trump has called the probe a witch hunt and has pointed out that no evidence has been discovered after well over a year of the ongoing investigation.