Blundering contractors were today labelled 'incompetent' after being blamed for causing huge tailbacks in and around Whitton.

Virgin Media's contractors have been accused of ignoring Transport for London's instructions when laying cables overnight under the A316 Chertsey Road, near Hospital Bridge Roundabout, in Whitton.

TfL said it gave permission for the road to be dug up, but said it must be done one lane at a time to avoid causing traffic disruption.

However, it says contractors attempted to get it all done in one night, digging up all five lanes, and when they failed to finish in time placing 'inadequate' plating over the trench. A spokesman for TfL said the covering was so weak and unsafe for traffic it appeared to bow under the weight of a single police officer.

As a result the road has been closed eastbound, causing miles of tailbacks, and reduced to a single lane westbound as TfL and Virgin Media's contractors work to repair the surface. At the height of the morning rush hour, cars were queuing all the way back to the A3.

A TfL spokesman said it was not known when it would be possible to reopen the road.

Leon Daniels, TfL's managing director of surface transport, said: "Once again, people's commute into London has been thrown into utter chaos because a utility company has decided to have a cavalier attitude to roadworks and once again caused chaos for thousands of London's commuters.

"This is unacceptable, unnecessary and hugely frustrating for all and I will be personally writing to the chief executive of  Virgin Media to ask them to explain how this easily avoidable disruption was allowed to happen."

A TfL spokesman added that its legal team was investigating what further action could be taken.

A spokeswoman for Virgin Media said: "We take this matter extremely seriously and are addressing our contractors failure to comply with the works authorised and agreed with TfL.

"We're working with TfL to resolve the issue urgently and regret, and apologise for, the concern caused to motorists in the area."

David Beaty, business strategy director for Virgin Media's contractor McNicholas, said: "McNicholas would like to extend a sincere apology to both road users and the authorities for the disruption and inconvenience caused today by works being carried out on the A316 Chertsey Road.

"A thorough internal investigation is being undertaken to ensure that this type of incident does not re-occur and we are co-operating fully with all parties involved. We wish to thank all the authorities for their support today in securing the successful re-opening of the Chertsey Road this afternoon."

The road is now fully opened in both directions but as of 5pm TfL warned queues would take some time to clear. Check here for the latest developments.