Michael Flynn’s sentencing hearing Tuesday ended without a sentence.

Instead, the presiding judge suggested Flynn, the former national security adviser to President Donald Trump, may need to continue cooperating with U.S. prosecutors.

“I cannot assure that if you proceed today you will not receive a sentence of incarceration,” Judge Emmet Sullivan told Flynn.

Flynn’s sentencing hearing in federal court in Washington took the surprise turn after Sullivan said Flynn had committed a “very serious crime” of lying to federal investigators while he was serving as a top military adviser to the president. The judge then delved into allegations revealed earlier this week that Flynn had taken money for a secret lobbying effort for Turkey while he worked for Trump’s campaign. Federal prosecutors told the judge in court Tuesday that such crimes could lead to as much as a decade in prison.

“Arguably, you sold your country out,” Sullivan told Flynn. “I’m not hiding my disgust, my disdain for this criminal offense,” he added, suggesting that Flynn reconsider whether it was in his interests to be sentenced Tuesday.

Both prosecutors for Special Counsel Robert Mueller and Flynn’s attorneys asked for leniency after Flynn provided information for multiple investigations following his guilty plea for lying to federal investigators. Flynn’s attorneys had said that he would continue to cooperate even after his sentencing.

Sullivan said that federal judges have a difficult time handing down sentences to cooperators when they don’t know the full extent of their assistance.

Following an impromptu break in the hearing, Flynn and his lawyers agreed to delay sentencing. A status report in the matter is due March 13.