The Tories have demanded a full investigation into the problems which resulted in a huge power cut which brought chaos to London's transport network.

Shadow trade and industry spokesman Tim Yeo said responsibility for the investigation lay with central government.

His intervention came as energy minister Stephen Timms demanded an urgent report from the National Grid.

Forum Response: EDF Energy

A spokesman for EDF Energy said: "Following a fault with high voltage power lines owned and operated by National Grid Transco (NGT) supplying parts of London, EDF Energy worked quickly to mitigate the problems resulting from the fault so that power could be restored to customers as quickly as possible."Faults on the NGT power supply lines caused them to shut down at around 6.20pm and all power was restored at 7pm. EDF Energy is keen to receive information from NGT about what caused this problem."

Forum Response: Institute of Directors

A spokesman for the IoD told ePolitix.com: ""The government itself has admitted in its recent energy white paper that the UK's energy infrastructure need updating. And now large scale power failures in London and North America are helping to focus the mind on security of supply as well.

"It seems that not only should we be concerned about security of supply of imported oil and gas but also of our own domestic energy infrastructure."