Leaders of the new combined authority must sign up doubting councils for the new body to be a success, Birmingham's top Tory has claimed.
Robert Alden, Conservative leader at Birmingham City Council, has welcomed the £1 billion devolution deal and plans for an elected mayor announced today but urged the leaders of the fledgling West Midlands Combined Authority to widen their membership.
Coun Alden (Erdington) said: "Here in the West Midlands region, we are the birth place of Shakespeare, the home of rugby, we started the industrial revolution that modernised the world, founded the football league, have the best chocolate in Cadbury, are leaders in the automotive industry.
"We now have a significant devolution deal and, if we can get the combined authority right, we won't just be a regional powerhouse, we will be the engine that drives the nation's economy in the 21st century.
"The West Midlands is back were it belongs at the top of our country's economy."
The new authority currently has seven core members - Birmingham, Solihull, Walsall, Wolverhampton, Dudley and Coventry - plus five associate councils including Tamworth and Cannock Chase and the three regional business groups called Local Enterprise Partnerships (LEPs).
Coun Alden added: "What is key now is to work with the non-metropolitan councils in the three LEP areas to get them signed up to our combined authority as well.
"If we can get this right and up and running soon, as a region we will be able to go back to the Government demonstrating how even more can be devolved down to our area."
While also welcoming devolution, the Solihull opposition Green Party has called for the fight against poverty to made a priority over economic growth.
Spokesman Scott Redding said: "Economies may grow but that growth doesn't always benefit everyone.
"We've seen that year-on-year growth hasn't translated into alleviating poverty in the most deprived areas of the West Midlands."
He added that, so far, the whole deal had been shrouded in secrecy and called for greater openness in future as well as details of how the public will hold both the combined authority and elected mayor to account.
Labour's MEP and likely mayoral candidate Sion Simon said the deal marked the end of the "stranglehold" government had had over the region for so long and raised hopes of further devolution to come.
He said: "This will be the start of a devolution process. Gradually, we need to take much fuller control of our own lives and decisions in the region.
"London does not know best. An elected mayor will provide vital, visible accountability while uniting the different parts of the region. The buck will stop there as it has with Ken Livingstone and Boris Johnson in London."