A BREXIT event and an anti-racism event are due to take place in Swansea on Saturday.
South Wales Police is aware of what is planned and, while acknowledging the right to peaceful and lawful protest, said “necessary action” would be taken against anyone acting illegally.
The party For Britain said one of its representatives had worked tirelessly to put the Brexit event on.
For Britain had inquired about staging it at Castle Square, but the Stand Up For Racism event is due to be staged there instead.
Concerns have been raised about leaflets denoting Swansea and Gower’s three MPs as “traitors”, which appear to have come from a different group altogether.
Speaking at a meeting of full council on April 25, council leader Rob Stewart warned of a “far right” element, and urged councillors who wished to support the Stand Up For Racism event to be vigilant.
“There is potential for disruption or for other issues to occur,” said Cllr Stewart.
A spokesman for For Britain said it was his understanding that a wide range of people would be attending and supporting “this important event”.
He said For Britain was concerned about the lack of the implementation of Brexit since the 2016 referendum, but that it was not a single issue party.
He said For Britain had policies which might have been considered centre left or centre right a few years ago. He claimed “left wing” Swansea Council opposed free speech by not allowing the event at the square and had gone into “full sulk mode”.
Cllr Stewart said the council had not prevented For Britain coming into the city, but that it was not able to hold a political rally at the square. He said Stand Up For Racism’s event was a community coh