Energy costs have been sent rocketing by Iran blocking the crucial Strait of Hormuz shipping route, through which a fifth of the world's oil and gas is carried, in response to the war.

The jump will equate to a rise of £18 a month for the average household using both electricity and gas, with households seeing an increase of 24% on their gas bills and 5% on their electricity bills. Standing charges are almost unchanged.

The energy cap covers 33 million households in England, Wales and Scotland. Regulation and bills are different in Northern Ireland.

The cap fixes the maximum amount customers can be charged for each unit of gas and electricity via variable tariffs. About 40% of bill-payers have fixed tariffs and are unaffected because their price will not change until the end of their fixed term.