Even 'commercially sensitive' information provided by developers as part of affordable housing viability assessments must be made available to councillors.

So says a backbench Labour motion due to be debated at Wednesday's meeting of Manchester City Council.

The motion — proposed by Didsbury East councillor James Wilson and supported by six other members, including one junior member of the council's leadership — comes as the row about affordable housing in central Manchester escalates. For the first time private rumblings of discontent — apparent for some time — are appearing in public.

The motion said: "This Council notes that developers have often used viability assessments to avoid their obligations to provide affordable housing."

The motion comes as the city council clashed with The Guardian over how much affordable housing had been built.

The Guardian report followed research for Greater Manchester Housing Action which argued that a £5.85B city centre housing boom had produced five affordable units in Salford, and none in Manchester.

The motion to be debated on Wednesday would require that viability assessments be published — with commercially sensitive material made available to councillors. At present viability assessments are not published.

The housing debate in Manchester is now shifting toward criticism of marketing city centre apartments to overseas buyers.

Both concern about viability assessments, and at large numbers of overseas investors, come ahead of fiercely fought city council elections in May.