Danny Alexander has said no-one should face a cut in state help if no suitable smaller property is available and all disabled claimants should be exempt.
In a direct message to the Conservative government, the Chief Secretary to the Treasury said the Liberal Democrats will "make the case for these new fairer rules."
Speaking to The Mirror he said: "If we can't convince our Conservative coalition partners, we will commit to these reforms in our 2015 manifesto."
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President Trump has scrapped protections for transgender students that had allowed them to use bathrooms matching their gender identity.
Prisons will be expected to reform prisoners as well as punish them under new proposals, set to be unveiled on Thursday.
Younger workers are missing out on pay rises, with people born in the 1980s earning £40 a week less than those 10 years older, studies show.