The letter being read out in churches today will urge people to preserve 'traditional marriage'.
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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