Health Secretary Wes Streeting has called for his former assistant to stand down as an east London councillor after the aide admitted indecent exposure.
Sam Gould, 33, a Redbridge representative, pleaded guilty to two separate counts at Barkingside Magistrates Court in Ilford on Monday.
The Labour councillor has been suspended from the party but "there is no process for his suspension" from Redbridge Council, the local authority says.
Mr Streeting, who said Gould had exposed himself to a mother and her daughter, said there were "no words to express his horror" at their ordeal, the trauma of which they would have to deal with for some time to come.
He added: "As soon as I was made aware of his arrest he was suspended, and as soon as the guilty plea was entered, I took immediate steps to sack him through official HR processes.
"There are no excuses for his appalling behaviour. I am calling for him, again, to resign as a Redbridge councillor immediately."
Kam Rai, leader of Redbridge Council, said he was "shocked and appalled" by the "inexcusable betrayal of his residents".
He said: "As soon as Mr Goulds arrest was communicated over the weekend, he was rightly suspended by the party.
"Unfortunately, there is no process for his suspension from the council. My heart goes out to the victims who have had to endure his despicable behaviour."
Gould, of Hornchurch, east London, was bailed until sentencing on 7 April.
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