Argentina’s libertarian president, Javier Milei, has won key midterm victories, backed by billions from the Donald Trump administration.
Mr Milei, a close ideological ally of Mr Trump, announced that his party had gained 14 Senate seats and 64 in the lower house in Sunday's vote, strengthening its presence in Congress.
Mr Trump called the results "a big win" for his ally, praising him for "doing a wonderful job" as his party's performance exceeded expectations.
"Congratulations to President Javier Milei on his landslide victory in Argentina. He is doing a wonderful job! Our confidence in him was justified by the people of Argentina," Mr Trump said in a post on Truth Social.
The US leader added that Milei "had a lot of help from us".
Speaking to supporters in Buenos Aires after the results, Mr Milei declared: "Argentines showed that they don't want to return to the model of failure."
He added that the victory would help him push his radical free-market agenda: "Today we reached a turning point. Today begins the construction of a great Argentina."
Mr Milei's government has managed to cut monthly inflation sharply, from 12.8% before his inauguration in December 2023 to 2.1% last month, while also securing a fiscal surplus.
The Trump administration extended a bailout potentially worth $40 billion (£30 billion) to help stabilise Argentina's peso. Mr Trump's support ahead of the vote included a $20 billion currency swap and a proposed $20 billion debt investment facility.
As part of its economic assistance to Argentina, Washington is also considering buying Argentine beef to bring down prices in the US.
That proposal has angered American cattle ranchers, but Mr Trump has downplayed their concerns.
"We're going to get the price of beef down, and I'm going to make sure the cattle ranchers don't get hurt," Mr Trump said.
Building momentum nationwide
The election results showed Mr Milei's party, La Libertad Avanza, winning in parts of the country long dominated by Peronism.
In the Buenos Aires province, a traditional Peronist stronghold representing nearly 40% of voters, La Libertad Avanza narrowly won edged out a win Sunday - just a month after the Peronists had defeated Milei's party there by 14 points in local elections.
Nationwide, La Libertad Avanza increased its representation in the House of Deputies, the lower chamber of parliament, from 37 to 64 seats out of a total of 127.
Axel Kicillof, governor of Buenos Aires province and the leading figure in the Peronist opposition, has criticised Trump for influencing the election.
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He argued that the billions in US Treasury and investment bank support would do little for ordinary Argentines struggling with Mr Milei's subsidy cuts and an economy forcing businesses to close.
"I want to make it clear that neither the US government nor JP Morgan are charitable societies," Kicillof said. "If they come to Argentina, it is for nothing other than profit, putting our resources at risk."
Mr Milei's push to deregulate the economy and eliminate tariffs earned him strong backing from Argentina's influential agricultural sector, helping his party secure a decisive victory in Santa Fe Province, a key hub for soybean production and processing.
The president has said he expects a cabinet shake-up after the election that could include members of the centrist PRO party, a frequent ally of the government in Congress led by former President Mauricio Macri.
(c) Sky News 2025: Trump hails 'big win' for ally Milei in Argentina's midterm elections
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