A lobby group representing Birmingham's young professionals has backed plans for a "Greater Birmingham".
But Birmingham Future, which represents professionals in the professional and financial services sector, called for further debate on whether there should be a directly-elected mayor.
The Institute for Public Policy Research (IPPR), a left-wing thinktank with links to Labour, called for the creation of a "city region" with a budget of #675 million to spend on economic development, regeneration, transport and training.
Business leaders have welcomed the proposal but rejected calls for an elected mayor to lead the region. The
British Chambers of Commerce has called instead for the creation of an executive committee, including the leaders of local authorities and business bosses.
Mike Whitby, leader of Birmingham City Council, supports an executive committee. But Chris Robertson, chairman of Birmingham Future, said it was important to have clear responsibility.
Mr Robertson said: "Having been involved with the report since the early stages, we are delighted with the authors' conclusions that Birmingham is both ready for and capable of taking on greater devolved responsibilities.
"As with all administrative changes, devolving power to city regions is likely to take time - a fact highlighted by the report's authors who state that the process is unlikely to begin before 2010. Clear lines of responsibility should mean that those charged with making important funding or strategy decisions will be directly answerable."