Spain has "definitively" recalled its ambassador to Buenos Aires, in a rapidly escalating row over comments made in Madrid by Argentina's President Javier Milei.

President Milei said the decision was "absurd".

At a far-right rally on Sunday, he had described the wife of Spain's left-wing prime minister Pedro Sánchez as "corrupt", without directly naming Begoña Gómez.

Spanish Foreign Minister José Manuel Albares summoned Argentina's ambassador Roberto Bosch the next day to demand a public apology from President Milei, but no action was taken.

Mr Albares described the case as unique in diplomatic history. "There is no precedent for a head of state who goes to another country's capital to insult its institutions and flagrantly interfere in its internal affairs," he said.

Spain had initially withdrawn its envoy, María Jesús Alonso, at the weekend for consultations but the foreign minister said on Tuesday that the ambassador would now remain in Madrid indefinitely. Argentina would no longer have a Spanish envoy, he said.

Mr Milei had been invited to the Europa Viva 24 conference by Spanish far-right party Vox, along with several other political leaders, ahead of European Parliament elections in three weeks' time.

While other far-right leaders spoke about migration and strong borders, President Milei targeted socialism, Spain's Socialist prime minister, and his wife.

"When you have a corrupt wife, let's say, it gets dirty," he said.

Last month, Pedro Sánchez threatened to resign when a preliminary inquiry was opened into allegations of corruption against Begoña Gómez made by a right-wing anti-corruption group. No charge has been levelled against her and the public prosecutor in Madrid said the case should be shelved for lack of evidence.

Mr Albares has not ruled out completely cutting diplomatic ties if no public apology is forthcoming from Argentina.

At a news conference on Tuesday he said Spain had no desire for further escalation, but the Government had an obligation to defend the dignity and sovereignty of its institutions.

For now Madrid will maintain its chargé d'affaires in Buenos Aires, but could go further.

Argentina's far-right president has been no stranger to controversy since he came to power last November, launching personal attacks on the presidents of Brazil and Mexico.

Doubling down on his remarks, he told Argentine TV that he had not accused anyone by name during his address in Madrid.

"I am not going to apologise from any point of view, if I was the one attacked," he told Todo Noticias.

Earlier this month Spanish transport minister Óscar Puente accused the Argentine leader of using drugs during his election campaign.

At the time, President Milei brushed off the "slander and insults", by suggesting the government in Madrid had more pressing things to deal with, and brought up the corruption allegations against Mr Sánchez's wife.

In his TV interview he asserted that relations with Spain would not break, as it was people not leaders that built a relationship.

In a further attack on the Spanish leader he said Mr Sánchez was "using it politically because he has problems and needs to polarise them".