The Church of England added that introducing gay marriage could also lead to challenges to civil partnership law, as removing the concept of gender from marriage while leaving it in place for civil partnerships would be unlikely to be "legally sustainable".
In a highly critical response to the Government's consultation on gay marriage which closes on Thursday, the Church of England said several "major elements" of the proposals had not been thought through properly and were not legally "sound".
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The comments are the latest twist in the row between the US and EU countries including Britain over trade tariffs.
St Paul’s Girls’ School in London was criticised by a former pupil over the exercise, which resulted in money going to charities.
‘They kept overtaking each other, so maybe the match will be closer than we expect,’ said Richard Nicholson, of Cannon Hall Farm, near Barns