The spat began when Spanish Transport Minister Oscar Puente, during a panel discussion Friday, suggested that Argentina’s President Javier Milei had ingested “substances” during last year’s election campaign.

A huge diplomatic row has erupted between Madrid and Buenos Aires after Spanish Transport Minister Oscar Puente suggested Argentina’s President Javier Milei was a drug user.

The spat began on Friday when Puente, during a panel discussion in Salamanca organized by his Spanish Socialist Workers’ Party, suggested that Milei had ingested “substances” during his election campaign last year.

“I saw Milei on television” during the campaign, Puente told a Socialist Party conference. “I don’t know if it was before or after the consumption … of substances.”

The minister also listed Milei among some “very bad people” who have reached high office.

Milei’s office released a statement on Saturday condemning Puente’s “slander and insults” while also attacking the policies of Spanish Prime Minister Pedro Sanchez.

The statement accused Sanchez of “endangering Spanish women by allowing illegal immigration” and undermining Spain’s integrity by making deals with separatists, while his left-wing policies brought “death and poverty”.

That provoked a rebuke from the Spanish foreign ministry, which said that “the Spanish government categorically rejects the unfounded words … which do not reflect the relations between the two brotherly countries and peoples.”

“The government and the Spanish people will continue to maintain and strengthen their fraternal links and their relations of friendship and collaboration with the Argentine people, a desire shared by all of Spanish society,” the ministry added.

The spat comes two weeks before Argentina’s “anarcho-capitalist” president visits Spain.

Milei will attend an event of the far-right Vox party and will be avoiding meeting Sanchez, Spain’s socialist head of government.

The two leaders have never had good relations.

Following the election of Milei, a right-wing populist who took office in December, relations between Argentina and Spain, ruled by a left-wing coalition led by Sanchez’s Socialist Party, have significantly cooled.

Sanchez supported Milei’s rival Sergio Massa in the election that brought Milei to power in December and has also not contacted the Argentinian leader since the victory.

Milei has, meanwhile, publicly supported Spain’s far-right anti-immigration Vox party. Vox leader Santiago Abascal also went to Buenos Aires for Milei’s investiture.

Milei has a history of spats with other world leaders.

He has described Brazilian President Luiz Inacio Lula da Silva as an “angry communist” and corrupt, and called Mexico’s President Andrés Manuel López Obrador “ignorant”.

The Argentinian president also called Colombia’s President Gustavo Petro “a terrorist murderer”, referring to him being a past member of a guerilla group. That insult prompted Colombia to expel several Argentine diplomats in response.