'Defective materials' meant that a large section of new road surface had to be ripped up moments after being laid on one of Norwich's busiest roundabouts.

As part of a £750,000 scheme to improve the safety of the Earlham Road Fiveways Roundabout, the busy junction was completely closed to traffic for resurfacing over the bank holiday weekend.

However, after it emerged there was a manufacturing fault with tonnes of the asphalt being used for the project, around 700sq/m of road surface had to be torn up and relayed.

The material, supplied by Tarmac, suffered an adverse reaction while it was being made when recycled asphalt was added to it during production - however it was still used.

As a result, the section had to be pulled up and re-laid and 200 tonnes of asphalt had to be returned to Tarmac.

However, transport bosses are still hoping the works will be completed on schedule and the whole roundabout can re-open to traffic "by the end of August".

A Transport for Norwich spokesman said: "The main Earlham Road access route was re-instated on Tuesday morning as planned and the partial closure and temporary signalling remain in place as planned until the end of August.

"A small quantity of the material used was deemed to be defective and was immediately returned to the supplier, but this was at no cost to the council or tax payer and should not affect the overall timescale of the project.

"The faulty area was re-laid on Wednesday evening without the need to close the roundabout and the scheme is due to be completed by the end of August as planned."

The project has seen the roundabout's central island made bigger and crossings on all three of the approaching roads upgraded to Toucan crossings, for pedestrians and cyclists.

Three of the roundabout's five junctions have been closed since June, however, the Earlham Road itself has remained opened under temporary traffic lights throughout - with the exception of the bank holiday weekend.

While the roundabout is scheduled to be in full use by Sunday, some works will still be carried out next week, such as testing the new traffic signals.