Fishermen have threatened to take legal action against the council if it fails to prosecute boaters who moor without authorisation on the Thames.

The Thames Anglers’ Conservancy claimed about 47 boats moored regularly without authorisation between Teddington and Staines.

The group claimed it was preparing to take Richmond Council to court for not enforcing byelaws and depriving anglers of their enjoyment of the river.

James Page, of the Thames Anglers’ Conservancy, said other authorities had successfully prosecuted the boaters, but Richmond Council said it did not have the powers to take action.

Councillor Virginia Morris, cabinet member for environment at Richmond Council, said: “When we receive complaints about illegal moorings our enforcement officers do encourage the owners to move them.

“However, we don’t currently have the power to force them to leave as no such byelaw exists, but we are seeking approval from the Government to create a byelaw to deal with this issue as soon as we can.

“Illegal moorings do affect people’s ability to use the Thames and enjoy its spectacular views, and I have every sympathy with the anglers.”

The authority does not have any official moorings on the Thames, and so any boat that drops its anchor against council land is deemed “unauthorised”.

Coun Morris added: “Although the council does not have any official moorings, a small number are provided by the Environment Agency. Boats moored against privately owned land are a matter for the landowner.”

Mr Page claimed more than 29 boats had been mooring without authorisation on the Richmond stretch of the river for more than three years.

Hampton Wick Councillor Tania Mathias said problems including sewage and blocking fishermen has led to tension between the boaters and residents.

Liberal Democrat Councillor Suzette Nicholson said people had also complained about boats in her ward, adding: “They just feel it’s really unfair.”