Plans to build half of Birmingham's new civic library at Eastside are being reconsidered by city council leaders.

Three months after the city council cabinet backed a Family Heritage and Archive Centre at Millennium Point, the possibility of a different site is now being discussed.

One idea is that the archives could be housed in the former Birmingham Municipal Bank at 301 Broad Street.

The proposal would place the archives about 200 yards from the Centenary Square site earmarked for the new lending and reference library.

The move, dubbed "crazy" by Labour, would enable the council's Conservative-Liberal Democrat coalition to dilute criticism about the decision to build a new library on two sites at opposite ends of the city centre.

The #147 million split-site scheme was attacked in a scrutiny committee investigation, which accused the cabinet of using "deficient information" and not properly taking into account the cost of building work when choosing sites at Millennium Point and Centenary Square.

The council paid #3 million in May to buy 301 Broad Street, a Grade ll listed building next to the former Register Office. The old bank is on the site of the planned #500 million Arena Central scheme, raising the possibility that planning-gain money could be sought from developers to help pay for the new library.

Council leader Mike Whitby stressed that no decision about where to put the archives had been taken.

Coun Whitby (Con Harborne) added: "As part of the proposals for the new Birmingham Library and Knowledge Centre and the distinct Family Heritage and Archive Centre, a number of different options for sites have been considered.

"As the scheme progresses, it has already been announced that the library will be built on the Centenary Square site. Work on the design process for that has commenced with the appointment of a project director.

"The administration is now turning its attention to the siting of the Heritage and Archive Centre and looking at a number of possible locations.

"This may include new-build at Eastside but at this stage it is prudent to keep all options open.

"It is worth remembering that under our proposals, Birmingham will get a brand new library and an impressive Heritage and Archive Centre."

The possibility of housing the archives at 301 Broad Street was raised by Birmingham Civic Society at a meeting with Coun Whitby a week ago.

Stephen Hartland, chairman of the society's planning committee, said: "This development is to be welcomed. It is a very positive move and shows that some real thought is being given to where the two elements of the new library should be located."

But the idea was dubbed "crazy" by Sir Albert Bore, leader of the Labour opposition group on the city council, who warned that the regeneration of Eastside would be hampered if the archives did not go to Millennium Point.

Sir Albert (Lab Ladywood) added: "Why are we putting all the eggs into one basket around Broad Street and Brindleyplace? This is a further blow to confidence in Eastside. People are getting very concerned at the lack of decision making and lack of vision being shown by the council leadership. There is a feeling that Birmingham is losing its way."

Sir Albert said a need to cut the cost of the library project could be driving the search for an existing building to house the archives.

"I just never believed that you could actually build two separate buildings of the right specification for less than the cost of one," he added.