The gaffe emerged as Chancellor George Osborne announced he will deliver an emergency Budget on June 22.
He said it will set out how the coalition Government will start tackling the UK's eye-watering £163billion deficit.
He also said he would detail next week plans to slash public spending by £6billion, while protecting frontline services.
Perhaps my arithmatic is flawed but £6billion cut from a £163billion deficit still leaves a £157billion deficit?