With less than two weeks on the job Argentina's new president, Mauricio Macri, has started a public row with Venezuela's government underlining that, in foreign policy at least, he meant what he said when he promised his election would bring "change."
"I want to explicitly ask for the liberation of Venezuela's political prisoners at this forum, in front of all the presidents," Macri said during a summit of the regional trading organization Mercosur in Paraguay on Monday, referring to a number of opposition leaders who have been jailed in recent years. "There can be no place within the countries that make up Mercosur for political persecution for reasons of ideology or for the illegitimate privation of liberty of those who think differently."
Macri's call for the release of Venezuela's jailed opposition politicians came during his first intervention in an international forum since his inauguration on December 10, when he replaced former President Cristina Fernández de Kirchner who maintained a personal friendship with Venezuela's President Nicolás Maduro.
His words could hardly have put a more abrupt end to the 12-year era in which Fernández and her predecessor and late husband — Néstor Kirchner — formed a solid block with the socialist administrations in Venezuela.
President Maduro was not at the meeting in Paraguay, but Venezuela's foreign minister, Delcy Rodríguez, responded to Marci's call with an equally harsh counterattack — her problem was that it appeared to have no basis.
"I understand that President Macri wants to ask for the liberty of these violent people," she said, referring to the prisoners. "I understand why because one of his first announcements [as president] has been to liberate those responsible for torture, disappearances, and murders during the Argentine dictatorship."
It is not clear why Rodríguez made the accusation. It may have been based on fears that this could happen if Macri were elected that were expressed prior to the election by one of the leaders of the Mothers of the Plaza de Mayo — the symbol of Argentina's struggle for justice in the wake of its military dictatorships.
Macri smiled as Rodríguez spoke. Later his foreign minister Susana Malcorra told a press conference that the president would not reply in person because "it's obvious that the information that foreign minister Delcy Rodríguez had is false."
Macri also provoked Venezuelan ire in comments he made about the congressional elections in Venezuela earlier this month which were won by a landslide by the country's opposition.
"We are pleased by the Venezuelan government's openness to accepting the result of the elections," Macri said. "I also ask for prudence from the opposition. We have to work without rest for a democracy that includes everybody."
Again Venezuela's foreign minister responded strongly, accusing the center-right former businessman of "interfering" in internal Venezuelan affairs. "You are defending political violence," Rodríguez said to the Argentine president.
The spat was barely reported in Venezuela. The presidential website did not mention the exchange though it did tweet a video of the foreign minister's comments accusing Macri of meddling. President Maduro retweeted another person's message thanking the minister "for defending the dignity of our homeland."
By contrast the events were covered intensely, and generally positively, in the Argentine media.
Macri could also count on the energetic support of the America's director of the US-based Human Rights Watch.
"It is an error to talk about intervention in internal affairs when universal rights are in question," José Miguel Vivanco said in a statement. "To hide behind sovereignty as an excuse to avoid international scrutiny for violations of human rights is a shameful tactic that is typical of authoritarian regimes with something to hide."
Macri's statements appeared to refer directly to Venezuelan opposition leader Leopoldo López who was jailed in February 2014 and accused of inciting violence in anti-government demonstrations. López's wife Lilian Tintori was present during Macri's victory celebrations in November.
During his campaign Macri had floated the possibility of seeking to expel Venezuela from Mercosur via the group's "democratic clause." His foreign minister has since said Argentina will not do this because of the opposition's congressional victory.
In the meantime, while it is far from clear where the public antagonism between the governments of Argentina and Venezuela will go from here, it does seem likely that sparks will now fly every time representatives of the two governments meet.
Follow Gaston Cavanagh on Twitter: @gastoncavanagh