Camden Council’s leader has branded as "unacceptable" an outgoing councillor’s covert social media activity, which prompted their resignation.

Cllr Lazzaro Pietragnoli (Lab, Camden Town with Primrose Hill) apologised on Monday (November 22) as he announced he was stepping down for making “a serious mistake at a difficult time in my life”.

His party’s leader and the head of the town hall, Cllr Georgia Gould, said the former mayor, who was most recently Camden Labour’s chief whip, was right to resign.

The departure follows reporting by the Camden New Journal which revealed Cllr Pietragnoli was secretly operating the Twitter account @PHillmum, which has now been deleted.

The profile posed as a mother-of-three living in social housing, praising himself as local councillor but making veiled attacks on politicians including former Camden mayor Cllr Maryam Eslamdoust and Islington MP Jeremy Corbyn.

In an email to the Labour group Cllr Pietragnoli, who was elected in 2002, said: “The events of the last few days have put an immense pressure on me and those around me, as well as the Labour group, and I have come to the view that the best way forward for all those concerned is for me to step down from the council.

“I would like to apologise to everyone in the Labour group for the upset I have caused. I made a serious mistake at a difficult time in my life and I am wholeheartedly sorry that I caused distress and offence.

“There are no excuses for my actions, and I am deeply sorry to my colleagues, constituents, and anyone this has impacted.”

Camden's opposition leader Cllr Oliver Cooper (Con, Hampstead Town) said Cllr Pietragnoli's behaviour brought the council and public life into disrepute.

"At a time when online social media abuse is high up the public agenda, it took an unbelievable arrogance and sense of impunity to use a poison pen account to try to bully people out of public service," he said.

"The fact that this abuse was tolerated poses serious questions about the judgment of the council leadership and their culpability."

Camden leader Cllr Gould said: “Lazzaro has been a hard-working and dedicated councillor for Camden Town and Primrose Hill, but his actions on social media were unacceptable and he is right to take responsibility and step down as a councillor."

Cllr Pietragnoli has now been removed from Camden's list of councillors, ahead of local elections in May.