At the time of the 2010 general election, the Conservatives promised a transferable tax allowance worth around £150 to married couples.
The Liberal Democrat leader Nick Clegg ridiculed the proposals as "patronising drivel that belongs in the Edwardian age".
His party later secured a provision in the coalition agreement allowing them to abstain from voting on the issue.
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There will be a few showers in the north, but otherwise dry for many with warm sunny spells before heavier rain in the south west.
David Davis is hoping to push Brexit withdrawal talks towards discussions on a future trading relationship between the UK and EU.
A fine start to Sunday but rain moves in from the southwest later on.