In a statement to the South American football federation CONMEBOL, the Argentinian club said the team would leave for Spain "Wednesday at 1400 local time (1700 GMT) in a charter flight from Ezeiza airport", AFP reported.
River Plate had earlier said it was opposed to moving the match against fierce local rival Boca Juniors from Buenos Aires to the Santiago Bernabeu in Madrid.
Coach Marcelo Gallardo had called it "absurd", adding that his side had lost home advantage.
River should have hosted the match at its own El Monumental stadium on November 24 but it was postponed after River Plate fans attacked the Boca Juniors team bus.
Several Boca Juniors players including Pablo Perez needed hospital treatment for injuries caused by shards of glass and others complained about the effects of inhaling teargas in the attack.
Boca then refused to play the match and it was postponed 24 hours, only to then be called off indefinitely the next day.
Boca petitioned CONMEBOL to be awarded the trophy, but that was rejected.
The first leg at Boca Juniors' Bombonera Stadium had finished 2-2.
CONMEBOL then switched the match to Madrid, a decision opposed by both Argentinian clubs.
On Monday, Boca and River put on sale the 5,000 tickets that each club has for fans living in Argentina. They cost 3,600 pesos (€84) – about a quarter of the average salary in Argentina.
In Spain, 20,000 additional tickets for River fans not residing in Argentina sold in a few hours, a source close to the organization told AFP.
Another 20,000 for Boca fans living outside the country went on sale from Tuesday.
The second leg of the Libertadores Cup takes place in Madrid on December 9.