Kylian Mbappe has described a Paraguayan politician as "despicable" and unworthy of her position after she made several racist remarks toward the France star.
Celeste Amarilla, who is a senator and member of Paraguay's Liberal Radical Party, posted comments on X after her country's defeat by France in the last 16 of the World Cup.
In response, Mbappe said on X: "Madame Celeste Amarilla, you are a despicable woman and unworthy of your position.
"You do not represent Paraguay, that country which has sweated passion and honour throughout the competition.
"Through your recklessness and your brazen racism, the entire world has already forgotten the journey and the historic effort that your players accomplished during this World Cup, making way for an incompetent woman who gives the worst possible image of her country.
"I will never allow people like her the freedom to spread their hatred and racism across the world."
French prosecutors have opened an investigation into aggravated public insult and incitement to hatred or violence following Amarilla's comments.
The Paris prosecutor's office said on Tuesday that it launched the probe after the national unit for combating online hate received a complaint from the French Football Federation (FFF).
When asked about the French prosecutors' investigation, Amarilla said she has not been formally notified of any legal proceedings and argued that France had no basis to pursue a case against her.
"To the French Football Federation, I'd tell them to hire a lawyer before talking nonsense," she told reporters on Tuesday.
The competition's joint-highest goalscorer, Mbappe, scored the only goal in the game from the penalty spot, as France progressed to the last eight of the World Cup.
The France Football Federation earlier condemned the comments in a statement:
"The racist remarks made by Paraguayan Senator Celeste Amarilla targeting Kylian Mbappé are utterly abhorrent and unacceptable. How can anyone make such comments?
"These remarks are criminal and deserve condemnation. They must be prosecuted, here and elsewhere. The FFF is referring the matter to the public prosecutor's office with a view to legal proceedings.
"The Federation offers its full support to its captain, its players and, more broadly, to all victims of such hateful remarks. More than ever, the FFF remains committed to fighting racism and all forms of discrimination.
"These comments bring shame on those who make them and those who spread them. The players of the French national team represent France; it is our country that has been insulted."
Tensions grew throughout the game, with multiple scuffles involving both sets of players and staff ensuing.
Didier Deschamps said that Paraguay, who had knocked Germany out in the round prior, used "every trick in the book" during their fierce clash. Despite Paraguay's perceived overly physical play, they didn't pick up a single yellow card during the game.
