River Plate are refusing to play in the rearranged Copa Libertadores final second in Madrid, saying CONMEBOL's decision to move the fixture outside Argentina is "incomprehensible".

South American football's governing body confirmed this week that the fixture between River and fierce rivals Boca Juniors will be held in the Spanish capital on December 9.

The original match, which was due to take place at River's El Monumental stadium, was postponed after a violent attack on the Boca team bus by opposition fans.

River confirmed on Friday that they had appealed against the decision to relocate the match and are now insisting they will not take part in the game, accusing CONMEBOL of pricing supporters out of attending.

"Following the presentation made yesterday, Friday November 30, before the South American Football Confederation (CONMEBOL), River Plate confirms its refusal to change venue," a club statement said.

"The club considers that the decision distorts the competition, harms those who acquired their ticket and affects the equality of conditions following the loss of local status."

River, who were fined $400,000 and ordered to play two CONMEBOL-organised games behind closed doors due to the bus incident, insist the actions of those who threw missiles at the vehicle "are in no way the responsibility of the club" as security forces should have been better prepared in the area.

They added: "More than 66,000 people attending the stadium waited patiently for about eight hours on Saturday and returned to the stadium for the second time on Sunday. Those same spectators are now denied – unjustifiably – the possibility of witnessing the spectacle, by virtue of the obvious difference in costs and distance to the chosen venue.

"It is incomprehensible that the most important 'Clasico' of Argentine football cannot take place as normal in the same country that in the coming days is hosting a G20 [summit]. Argentine football as a whole and the Argentine Football Association (AFA) cannot and should not allow a handful of violent people to impede the development of the Superclasico in our country."

Boca and River played out a 2-2 draw in the first leg at La Bombonera.