The US has pulled back part of the sanctions relief it granted Venezuela last year after the South American country’s highest court blocked the presidential candidacy of an opposition leader.

The Department of the Treasury gave companies transacting with Venezuela’s state-owned mining company until February 13 to wind down operations having allowed transactions in October after President Nicolas Maduro’s government agreed to level the playing field ahead of this year’s presidential election.

On Friday, the country’s highest court upheld a ban on the candidacy of María Corina Machado, a long-time government opponent and winner of the primary held by the US-backed opposition faction.

She won the opposition’s independently run presidential primary with more than 90% of the votes despite the government announcing a 15-year ban on her running for office just days after she formally entered the race in June.

The long-time government foe was able to participate because the primary was organised by a commission independent of Venezuela’s electoral authorities. She insisted throughout the campaign that she never received official notification of the ban.

In December, Ms Machado filed a claim with Venezuela’s highest court, arguing the ban was null and void and seeking an injunction to protect her political rights. Instead, on Friday the court upheld the ban, which alleges fraud and tax violations and accuses her of seeking the economic sanctions the US imposed on Venezuela in the last decade.

She called the court ruling blocking her presidential candidacy “judicial criminality” and vowed to stay in the race, declaring that the decision embodies the ruling party’s fear of having to face her at the polls.

Ms Machado, surrounded by supporters and other opposition leaders, told reporters she expects government repression to increase against her and her team, because it is “the only tool they have left” to stop adversaries.

But, she said, “the best option” for Mr Maduro and his allies is “to negotiate with us a peaceful transition”.

Friday’s ruling came more than three months after Mr Maduro and the US-backed opposition, known as the Unitary Platform, reached a deal to work on basic conditions for a fair election in the second half of 2024, invite international electoral observers and create a process for aspiring presidential candidates to appeal their bans.

The agreement triggered some sanctions relief in the oil, gas and mining sectors. But the US government threatened to reverse some of the relief if Venezuela’s government failed to reverse bans preventing Ms Machado and others from holding office and did release political prisoners.

The impact of Monday’s decision affecting Compania General de Mineria de Venezuela, known as Minerven, was not immediately clear. The license authorising transactions was intended to see some of the illegal trading of gold in Venezuela move to the legal market.

Sanctions relief in the oil and gas sectors remain in place.

“They need to make the right decisions here and allow opposition members to run for office and release the political prisoners that they’re holding right now,” White House National Security spokesman John Kirby told reporters, mentioning some of the steps Mr Maduro agreed to take as part of the agreement signed in October in Barbados.

The Organisation of American States and about 30 political leaders from Spain and Latin America have also condemned the court’s decision.