"An agreement was reached with Atletico and Thiago, but it will be announced after the World Cup," said a source from River's management following negotiations held in Spain.
The 25-year-old striker, a World Cup winner in 2022 and currently taking part in the tournament in the United States, is set to leave European football in search of the playing time he was unable to secure in Spain, a source close to the player told Reuters.
Almada's transfer to River will be finalised for around 20 million dollars for 50% of his registration rights, according to reports in the Argentine press.
Almada began his career at Velez Sarsfield, before joining Atlanta United, Botafogo and Olympique Lyonnais and then moving to Atletico. Last season, he made 40 appearances across all competitions, and scored four goals.