Gas works will see a city centre road become “pedestrianised” for four months.

Maintenance work costing £70,000 will begin in St James’s Street in Brighton at the start of next month, forcing those taking part in the Brighton Marathon to have to dodge them during their run.

But businesses in the road are worried the work could cost them thousands of pounds in trade at their busiest time of the year.

The work will take place in stages and is expected to finish by the end of June.

During this time buses will be diverted via Marine Parade.

Roger French, the managing director of Brighton and Hove Buses, confirmed the bus stop outside Morrison’s would remain in operation throughout.

Tim Hutchings, the race director for the Brighton Marathon, confirmed the works would not affect the route of the race on April 19.

He added covers were to be placed over any open trenches along the route.

A spokesman for Southern Gas Networks said the replacement of the 300 metres of cast iron gas main with polyethylene gas pipes would last for up to 80 years.

He confirmed the road will be closed to through traffic and apologised for any inconvenience it may cause.

The spokesman added any queries that shops had about compensation should contact the company on 0845 070 1431.