Ed Miliband is expected to point out that 3.6 million households - including one million with children - are now privately-rented accomodation.
"We cannot have two nations divided between those who own their own homes and those who rent", the Labour leader will say.
"There are too many rogue landlords and agencies either providing accommodation which is unfit or ripping off their tenants", he is set to add.
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England have been beaten by nine wickets against Pakistan in the first Test at Lord's.
Mayor of London Sadiq Khan is backing the scheme.
Sunday will be a fine day across much of Scotland and northern England, with much less coastal mist and low cloud than yesterday.