The easing of the targets will be seen as a climb-down in the face of the public outcry over the CSA's pursuit of absentee fathers in order to support their children.
But ministers will defend the CSA against a Commons attack by Labour. The debate has been timed by Labour to coincide with publication of the report.
Ministers will point out that the CSA saved more than pounds 400m on benefits in the year to April - an improvement on the pounds 313m saved by the Child Support Unit in 1992- 93 and the pounds 283m saved by the Benefits Agency in 1991-92.
'We are not planning to say anything new in today's debate. We are going to show that the CSA is doing a good job, and that it is here to stay,' one ministerial source said.
Ministers deny any climb- down. Targets that were set for the first year were a 'stab in the dark', they said. Targets set for next year will be based on the outcome of the first year in operation and will therefore be more realistic. The agency will be under continued pressure to deliver savings, however. The Treasury is pressing the social security department to halt the rise in social security spending as part of the annual public spending review.
The Commons Select Committee on Social Security is preparing a report on the operation of the CSA. Its criticism will include the operation of the rule preventing 'clean break' settlements between couples from being taken into account when maintenance payments are fixed.
The CSA makes no allowance for husbands who agree to hand over houses or lump sums to their partners in lieu of maintenance.