At least four abseilers were seen descending from the room of Basel's St Jakob Park stadium with a banner protesting against Arctic oil drilling by Russian energy firm Gazprom.
Schalke, the German team playing against Basel, display the Gazprom sponsor on the chest of their playing shirts.
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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