The Football Association has been accused by South American Confederation CONMEBOL of damaging Edinson Cavani's reputation over its decision to suspend the Manchester United striker for an offensive social media post.
CONMEBOL said the FA judgement did not "consider the cultural characteristics and the use of certain terms in everyday speech in Uruguay".
Cavani was handed a three-match ban on New Year's Eve for using a racial term in a social media post.
The 33-year-old had replied to a message congratulating him on his match-winning display against Southampton in November with a post using the Spanish word 'negrito'.
The word translates as 'little black person'. It is commonly used as a term of endearment in Uruguay, and other Spanish-speaking countries, but it is considered offensive elsewhere.
Cavani deleted the post, apologised and chose not to contest the misconduct charge out of respect for the FA's fight against racism within football but insisted there was no malicious intent.
On Monday, the Uruguayan players' union called on the FA to overturn Cavani's ban, describing its decision as "a true discriminatory act" and "against Uruguayan culture", and CONMEBOL has now followed suit.
In a statement published on Tuesday, the governing body for football in South America said: "CONMEBOL expresses its solidarity with the player Edinson Cavani, sanctioned by the Football Association of England.
"The disciplinary measure for the outstanding player from the Uruguayan team clearly does not consider the cultural characteristics and the use of certain terms in everyday speech in Uruguay.
"The judgment of these types of statements, within the framework of a process that can lead to penalties for the athlete and that affect his reputation and good name, must always be carried out taking into account the context in which they were made and, above all, cultural peculiarities of each player and each country.
"CONMEBOL condemns and will always condemn with the greatest energy any racist or discriminatory manifestation, but the specific case for which Cavani was sanctioned does not constitute one of them."
Cavani has already served one game of his three-match ban and will miss Wednesday's Carabao Cup semi-final against Manchester City and Saturday's FA Cup third-round tie against Watford.
He was also fined £100,000 and must complete an education course as part of his punishment.
