First-time buyers need an average income of £60,000 to get on the housing ladder in Merton, new figures show.
The figures were released as the borough's councillor for housing said he "meant business" in demanding more affordable flats and houses in big developments.
Merton Council said buyers looking for a one to two bed property in the borough, of average market value, would need a £60,300 income based on a mortgage totalling 3.5 times that figure and a 10 per cent deposit.
The figure, which would drop to about £53,600 for buyers able to offer a 20 per cent deposit, suggests the average price for a first home in the borough is about £230,000.
Reacting to the figure councillor Martin Whelton, cabinet member for housing, said: "Merton is crying out for more affordable homes.
"A lot of developers will try and get around it but Merton means business when it says 'we want 40 per cent'."
The figure is included in the borough's new core strategy - a guide for planning policy.
It relates to the percentage of homes in new developments that must be available at reduced cost through housing associations or Government-backed programmes like key worker and shared ownership schemes.
The level relates to developments in the borough of more than 10 properties.
Last month research by pressure group the Countryside Alliance found the number of affordable homes built in England, Scotland and Wales in 2010/11 was 176,000 below councils' target levels.
Housing issues were discussed during a conference at Morden's Civic Centre last Thursday (September 8). The event was attended by more than 100 people, including council staff and representatives from the voluntary sector.
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