The Treasury is looking to cut billions of pounds in welfare and other government departments amid expectations the chancellor's fiscal headroom has been wiped out.
The BBC reports the "politically painful" cuts are designed to reduce the growth in health-related benefits.
The department will put the proposed cuts to the Office of Budget Responsibility (OBR), the official forecaster, on Wednesday ahead of Rachel Reeves’ first Spring Statement later this month.
Sources said it was evident that "the world has changed" since the Budget last October, when the OBR indicated that Chancellor Rachel Reeves had £9.9billion in headroom against her self-imposed borrowing targets.
The Treasury will inform the OBR of its "major measures" to put public finances back on track to meet the chancellor's self-imposed rules.