US special counsel Robert Mueller has told a federal court that President Donald Trump's former National Security Adviser Michael Flynn gave "substantial assistance" to the Russia investigation and should not get jail time.
Federal sentencing guidelines called for Flynn to be sentenced to between zero and six months in prison and face up to a $9,500 fine.
According to the filing, Flynn sat for 19 interviews with the special counsel and other Justice Department offices, and his early cooperation gave prosecutors a roadmap for their Russia investigation. It may have helped encourage others to cooperate, it stated.
Mueller's office said Flynn assisted it "on a range of issues, including interactions between individuals in the presidential transition team and Russia." The rest of the sentence-long description of how Flynn helped in the Russian interference investigation was redacted, CNN said in a report.
Last week, Trump's former attorney Michael Cohen pleaded guilty to lying to Congress about his work on the proposed Trump Tower Moscow during the 2016 campaign and prosecutors accused former Trump campaign chairman Paul Manafort of violating his cooperation agreement by lying to the special counsel.
Last December, Flynn pleaded guilty to one count of lying to federal investigators in January 2017 about his contacts with the Russian Ambassador to the US and agreed to cooperate with Mueller's investigation.
The filing also rehashed his misstatements to Federal Bureau of Investigation agents, including a second series of lies he told to the Justice Department regarding his contacts and work for the Turkish government.
Flynn had a brief stint as National Security Adviser and was forced to resign on February 13, 2017, following revelations that he discussed sanctions with then-Russian Ambassador Sergey Kislyak and that the Justice Department had warned the White House that he was vulnerable to blackmail by Russia.
Months after his resignation, Flynn agreed to cooperate with Mueller's investigation.
(With inputs from agencies.)