Spain on Saturday denounced comments by Argentina's presidency which had accused the Spanish government of bringing "poverty and death" to its own people.
The office of Argentinian President Javier Milei had published a statement on X, accusing Prime Minister Pedro Sanchez of damaging Spain's economy and stability.
The post appears to have been in reaction to earlier comments from Spanish Transport Minister Oscar Puente who had suggested Milei is on drugs.
"The Spanish government categorically rejects the unfounded words... which do not reflect the relations between the two countries and their fraternal people," the Spanish foreign ministry said.
Milei's office also accused Sanchez of "endangering the unity of the kingdom, by sealing an agreement with the separatists and leading Spain to its ruin", an allusion to a pact Sanchez's Socialist Party struck with Basque and Catalan regionalist parties to form a government.
Milei will travel to Spain in two weeks for an event on May 18 and 19 organised by the far-right opposition party Vox, which is in a race with the Socialists in next month's European elections.
