SPIRALLING energy tariffs sparked a further jump in inflation today and left the Government facing a bigger-than-expected bill for state benefits.

In a further sign of the misery faced by UK households this year, CPI inflation rose to 5.2% last month from 4.5%, equalling the record high of September 2008 and dwarfing average wage growth of just 1.8% a year.

The Office for National Statistics (ONS) said gas and electricity jumped 13% and 7.5% respectively, food shot up 6.4%, communication costs, driven by mobile phone charges, increased 5.9% and transport prices gained 8.9% on a year ago.

September’s inflation rate is traditionally used to calculate April’s rise in state benefits, although the Government has yet to confirm this will happen.

If it does, the single state pension will increase by £5.31 to £107.46 a week, while jobseeker’s allowance will increase by £3.51 to £71.01 a week.

At a time when Chancellor George Osborne is attempting to reduce borrowing levels, the Institute for Fiscal Studies estimates the inflation spike will add an unexpected £1.8 billion to Treasury benefit calculations for 2012/13.

However, the figures are also used to determine business rates, which could result in companies paying an extra £1.3 billion next year, including £350 million more from the hard-pressed retail sector.

Jonathan Loynes, chief economist at Capital Economics, said the unexpectedly sharp rise in September’s figures had been a “nasty surprise”.

The update from the ONS also highlights the pressure on those who are reliant on savings interest to help pay for rising food and fuel bills.