Labour mayoral candidate Sadiq Khan has claimed affordable housing is “a million miles away” from what the Conservatives are promising.
In a debate held by BBC London, he accused Conservative Zac Goldsmith of subscribing to the view that a house worth £450,000 is “affordable”.
But Mr Goldsmith dismissed his views as “nonsense”.
The candidates were asked by an audience member what they saw as an affordable home.
Mr Goldsmith did not name a figure, saying an affordable housing policy was one that enabled an “average Londoner earning an average income to get the keys to their first home”.
He acknowledged “we do have a housing crisis in London” and said the “only long-term solution is to increase supply”.
Mr Khan countered that affordable house is “not £450,000 – which is the figure Zac is scared to mention”.
He was referring to Mr Goldsmith’s support for the government’s Housing and Planning Bill, under which starter homes will be sold at a discount of at least 20% of market price of less than £450,000 in London.
Mr Goldsmith hit back: “That is nonsense. We’ve already had this argument and you backed down – don’t do it again just because we’re on TV. It’s absurd.”
Mr Khan said he would limit rent to a third of average local earnings and enable people to part-buy part-rent with a deposit of £5,000, reiterating his ideas were “a million miles away from half a million pounds, which is what Zac thinks is affordable”.
Liberal Democrat Caroline Pidgeon committed to retaining the Olympic precept in order to invest in council housing, telling the audience: “I’m going to put money into this – I’m not just talking the talk.”
The Greens’ Sian Berry said she would call the prime minister on her first day in office and “tell him we need the power to control our rents”.
UKIP candidate Peter Whittle dismissed talk of affordable homes as “platitudinous”, saying: “Anyone who thinks the housing crisis is not linked to uncontrolled migration is in denial.”
The full exchange can be seen on BBC One in London on Monday from 22:45 BST.
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