Energy group SSE says it will increase tariffs by 9% on average in a move impacting around 5 million electricity customers and 3.4 million gas customers.

SSE will introduce the bill hike on October 15 and said it comes in response to energy price increases in wholesale markets, as well as rising costs of using the National Grid network.

The UK's second largest energy firm, formerly known as Scottish & Southern Energy, said it will cap bills following the October price rise until at least the second half of 2013.