Prof Mann is at loggerheads with the Government over nutrition public health policy, which is being reoriented to focus on pregnant women and infants. Prof Mann said this was not an evidence-based approach to combating diabetes and obesity.
The new regime replaces the axed Healthy Eating Healthy Action (HEHA) programme.
Funds would now be contestable, rather than distributed through district health boards.
It would focus on maternal and child nutrition and physical activity, while HEHA had a broader focus on combating obesity.
Calls for tender were supposed to be issued from last month.
Ministry of Health national services purchasing director Jill Lane said the ministry was still working on the project, and over the "coming months" requests for proposals would be issued.
Ms Lane said, via a spokesman, the prime minister's chief science adviser, Prof Sir Peter Gluckman, had advised that since preconditions for obesity were set very early, maternal and newborn nutrition was the best long-term investment.
Prof Mann said none of the people he would expect were consulted about the new programme, including the national diabetes service improvement group, of which he is a member.
Decisions had come from "on high", and there had been no debate.
"It does not matter a hoot that it's delayed," he said.
Prof Mann has had a strong reaction from members of the public to criticisms of the Government's nutrition policy he made at this month's World Diabetes Day in Dunedin. Many members of the public had approached him since with their messages of support for his stance, he said.
Funding for HEHA programmes ended on June 30.