Simon Hughes Mr Hughes told the BBC that his party and the Conservatives had four areas of disagreement Deputy leader Simon Hughes has renewed the Lib Dems\' attack on Conservative plans for married couples\' tax breaks. Mr Hughes, speaking after reports party leader Nick Clegg is to criticise the idea in a speech on Monday, also denied the issue showed coalition tensions. Mr Hughes told BBC Breakfast that marriage tax breaks was one of four areas in the coalition agreement where the two parties had agreed to differ. The other areas were nuclear power and energy, and tuition fees, he said. Conservative leader David Cameron said in his party conference in October: \"Marriage is not just a piece of paper. It pulls couples together through the ebb and flow of life. \"It gives children stability. And it says powerful things about what we should value. So yes, we will recognise marriage in the tax system.\" Mr Hughes was asked whether the idea that Mr Clegg was going to criticise the idea was a sign of growing differences in the coalition. He dismissed that suggestion, saying: \"There were four areas identified in the coalition agreement as being areas where there would be a difference. \"One was married tax breaks for married couples, where we have always taken the view that if people have been together, they shouldn\'t have a differential tax treatment from people who have been married. \"I have a Godchild whose parents have been together happily in a wonderful family for 25 years - they\'re not married. Should they have a different tax position (from a couple who are married)?\"