The payment of €150 a month to parents who keep their children at home would most likely drag money away from plans to expand and improve state-subsidised day care facilities, a new national education report published on Wednesday warned.
The report, commissioned by the federal and state education ministries, warned that the government's targets for increasing the number of kindergarten places might be missed if the benefit were introduced.
The benefit, known as Betreuungsgeld, has been pushed by the Christian Social Union (CSU), Bavarian sister party to Chancellor Angela Merkel's Christian Democratic Union (CDU), despite heavy political opposition from within the government coalition.
The academics who wrote the report also pointed to recent studies indicating that children who have completed at least three years in day care or kindergarten before starting school generally have better reading skills.
The report also found that even children from families with a higher educational background - who tend to have better reading comprehension skills - benefit from attending day care.
One statistic in the report was particularly alarming - around a quarter of German 3- to 7-year-olds are classified as "needing linguistic assistance," especially those from non-German families or with parents with a low standard of education.
Despite repeated expert warnings that the benefit will damage the education of disadvantaged children, Merkel's government is determined to pass the controversial bill before parliament goes into summer recess.
“The report is the opinion of the experts, not the opinion of the government,” said a government spokesman.
The Deutsche Tafel, a poverty campaign association, also came out against the plan on Wednesday. It said the payments could well have a negative effect on women and migrants working, and thus depress their incomes.
The day care facilities for children should rather be expanded in order to enable parents of large families and lone parents to work more and thus earn more, said Gerd Häuser, head of the association.