River Plate said on Saturday they have refused to play the Copa Libertadores final against Boca Juniors in Madrid.
The match between the Argentine arch-rivals has been moved to Real Madrid's Santiago Bernabeu stadium after it was twice postponed last weekend after River Plate fans attacked the Boca Juniors team bus.
The match is due to be played in the Spanish capital on December 9, but River Plate said they "confirmed their rejection of the change of location".
In a statement on the club's website, River said it was "incomprehensible" that the match had been moved to Spain.
"It is incomprehensible that the superclasico cannot take place as normal in the same country where a G20 summit is currently taking place," the club added.
World leaders including US President Donald Trump and Russian leader Vladimir Putin are attending the G20 summit in the Argentine capital this weekend.
The winners of the Copa Libertadores - South America's equivalent of the Champions League - will claim the last remaining place in this month's Fifa Club World Cup in the UAE.
The contest is tied at 2-2 after the first leg at Boca's Bombonera Stadium, which was also postponed by 24 hours but due to weather.
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