The worst economic outlook since the early 1990s will be the bleak backdrop to the pre-Budget report.
Its has taken on the air of an emergency Budget and will be the most important financial statement delivered since Labour came to power in 1997.
The prime minister and the chancellor have had to make a critically important judgement.
Get it right and their policies may soften the blow of recession without frightening the financial markets.
Get it wrong and government borrowing becomes ever more difficult to finance with tax revenues falling in a recession-gripped economy.