Dublin City Council wants a cap on the size of groups on walking tours of the city.
The Sunday Times reports the council has written to Fáilte Ireland to say the groups should be capped at 26 people.
Officials said the groups are clogging up footpaths and obstructing pedestrian traffic.
Independent councillor Mannix Flynn brought a motion on the issue late last year.
He said the situation is getting out of hand, and Dublin needs to make sure everyone has a good time.
Mr Flynn said: "Simply going around with 100 people on a walking tour through the streets of Dublin is just not safe and it's wrong.
"In other jurisdictions where this was happening, like Barcelona, London, Berlin, they curtailed this, they actually brought it down to around 26, 27 individuals, because it was literally blocking up the city."
The Independent councillor is also looking for a licencing system for tour guides.
He said some free tours are getting far too big and causing huge disruption in the city.
He said: "Barnardo Square, which used to be a lovely place to sit and have a sandwich and meet people, not a lot of people go there because it's surrounded by walking tour groups and there is the obligatory photograph where they all scream into the photograph 'Dublin'.
"At 9 o'clock this morning a group was screaming its head off into the camera, that group consisted of about 110 people."