After months of undercover work, taking notes and examining all data collected, I have come to the conclusion that if suddenly cars stopped entering Sainsbury's at Heyford Hill, Oxford, those trying to get out on to the roundabout wouldn't succeed.

It is only the cars going into the supermarket which allow the cars to exit from it.

This cannot be right and surely cannot be safe, can it?

Traffic lights are what the motorists and pedestrian shoppers need.

Of course, it all comes down to money, I suppose.

If Sainsbury's had any sense, it would put up the money for their installation.

At peak times, it can take 12 minutes to exit the supermarket on to the roundabout.

I know my old pal, Vim Rodrigo, has mentioned this problem in the past, but something needs to be done now, before a major accident happens there.

Tesco, at the Cowley Retail Park, is a pleasure to visit, with traffic light control at the main roundabout.

Come on, Sainsbury's and county councillors, get together and do the decent thing.

CHRIS BOSWELL Williamson Way Rose Hill Oxford