Hammerson dropped its plans for a £400m shopping centre last summer leaving the council looking for a new development partner.
The local authority said it would use the loan to buy buildings needed for its planned “New Retail Quarter”.
Labour councillor Leigh Bramall told the BBC a number of developers were interested in the project but if necessary the council would develop the area itself.
Plans for the revised scheme extend to 600,000 sq ft with a development value of £165m.
Demolition work is expected to begin next year with construction completed in 2019.
The original plan was for a large £400m shopping centre but it was put on hold due to the economic climate in 2007 and the council severed ties with Hammerson last October after repeated delays.
Bramall said: “The world’s changed and it’s probably unlikely that we’re going to get a similar all-in-one scheme with one single developer.
“The big difference between this proposal and the previous one is that this is the council taking control of the scheme to drive it forward.”
The loan will be repaid using profits from the scheme, the council said.