Changes are needed in the way the East of England Development Agency's (EEDA) flagship Investing in Communities (IiC) project is run, says a new report.
EEDA works to bring investment to the region
The East of England Regional Assembly (EERA) said in the review that it praised much of the work, regenerating areas in the East, carried out by IiC.
But the report also said there was a "lack of consistent" advice from EEDA, and highlighted other concerns.
EEDA welcomed the review and added it was making improvements to IiC.
The findings of a major scrutiny review by EERA are to be used to help deliver improvements to the IiC programme which funds community regeneration projects in the region.
IiC is one of four core funding programmes of the EEDA and was launched in December 2003. Its current budget is £100m over the four-year period 2007 to 2011.
The review, undertaken by a five member panel of the Assembly, supported the overall aims and structure of the IiC programme but found that implementation could have been better.
Chris White, leader of the Liberal Democrat group on the Regional Assembly said: "The Assembly must continue to take a close interest in this scheme over the next 12 months to see that improvements are made."
He added there were also issues over the general effectiveness of EEDA, over which the Assembly should take an interest.
He said: "The Assembly needs to challenge EEDA more robustly as an institution to ensure that it is effective in delivering its work programme as a whole not just IiC."
EEDA and EERA covers an area including Bedfordshire, Cambridgeshire, Essex, Hertfordshire, Norfolk and Suffolk.