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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Delicately worded memo by then press chief from 1985 is among cache of newly released documents from former PM's private files.
Cloud and showery rain may linger across the far northwest throughout Saturday.
Supporters of the British man who is awaiting release from Guantanamo Bay spoke to ITV News about their concerns for his health.