Leavesden Studios is a “little gem” that can transform south-west Hertfordshire into the region's film capital, the Mayor of Watford said.

Dorothy Thornhill added, however, that plans from Warner Bros. to invest £100million into the former airfield site would be considered “carefully” to assess how increased traffic could affect the town's transport infrastructure.

The film company, which currently leases Leavesden Studios, last week announced plans to buy the site outright and has submitted planning applications with Three Rivers District Council and Watford Borough Council for expanded production and filming space, two new permanent stages and other enhanced facilities.

The studios are best known as the home of Harry Potter, as every installment of the boy wizard's adventures have been filmed there. Production of the final film in the series, Harry Potter and the Deathly Hallows, which will be released in two parts, is due to finish this summer.

It has also been the location for Charlie and the Chocolate Factory and The Dark Knight.

Under Warner Bros. plans, there are also details for a small visitor attraction to allow fans to tour some of the sets used in major blockbusters.

But the company stressed this would not lead to a huge number of visitors to the site, as appointments would be by pre-booking only.

Though the studios predominantley occupy land within the boundaries of Three Rivers District Council, Mayor Thornhill said the issue of how much traffic any attractions would bring would be discussed at Watford Town Hall.

She said: “We have always argued that although it's technically on their land, the impact is on us. The issue will be how much traffic generation having an attraction will have with it. Obviously, we will be looking at the planning application carefully.”

The Mayor added: “Warner Bros. Watford has a ring about it. It also cashes in on what we have already got.

“Leavesden Studios is a little gem and Screen East are very strong in the region. If we can build that up though economic development based on film that will really be quite special to this part of Hertfordshire and bring specialist jobs too.

“There's a real opportunity here if people are prepared to grasp it.”