Energy companies have been told by Ofgem that they must give customers a 30-day warning before upping prices, energy conference delegates may want to hear.

Companies providing oil and gas must also inform consumers 30 days in advance of any tariff changes which could leave them worse off.

The utilities watchdog made the ruling this week, after promising recently that sweeping pricing reforms would be enforced for all energy companies. A spokesman said that current tariffs were "bamboozling" for customers.

Andrew Wright, Ofgem’s senior partner for markets, said: "Today’s changes will again show that we are serious about making sure suppliers play it straight with consumers.

"We believe that 30 days advance notification of price increases, coupled with our new proposals for more transparency and an end to complex tariffs, will give consumers more power to make informed switching choices."

Currently, companies have up to three months after a change has been made to inform customers. ADNFCR-3554-ID-19954291-ADNFCR Get Adobe Flash player