A prison sentence of up to 6 months was proposed by US special investigator Robert Muller for former assistant of the Trump election campaign, George Papadopoulos.
Muller, the head of the investigation into the alleged Russian involvement in the 2016 elections, said such a proposal was "justified and correct".
Papadopoulos admitted that he had been lying about his contacts with the Russians while he was a member of the Trump team.
The conviction is due to be announced on 7 September.
"The government does not take a stand on a specific penalty that should be imposed, but it suggests with all due respect that a prison sentence ranging from the stipulated limits from zero to six months is appropriate and fully justified," he says. Mr Muller added, that Papadopoulos was lying to the FBI about his contacts with the Russians.
Papadopoulos, a Chicago-based international energy lawyer, is one of three former Trump officials who admitted lying to the investigators. The other two are former security advisor Michael Flin and businessman Richard Gates, who was deputy campaign president.