A federal appeals panel has thwarted an ally of Venezuelan President Nicolas Maduro's attempts to be recognized as a foreign diplomat, leaving it to a lower court to decide for now whether he is immune from prosecution.

The Eleventh Circuit Court of Appeals panel did not rule Monday on the merits of businessman Alex Saab's argument that his detention, during a refueling stop on his way to Iran, violated U.S. law and numerous international treating protecting diplomats.

Instead, it said it was an issue best decided by the Miami federal judge overseeing the criminal case against Saab, meaning that it could still take up the matter at a later date.

"The parties did not have the opportunity to fully develop the record, and the district court did not have the opportunity to weigh the evidence, concerning Saab Moran's claim," the appeals panel said in its brief ruling, "Accordingly, we remand the case to the district court to consider in the first instance whether Saab Moran is a foreign diplomat and immune from prosecution."

Saab's attorneys have argued that he was traveling to Iran as a duly appointed special envoy of Maduro's socialist government when he was arrested on a U.S. warrant nearly two years ago in Cape Verde. They've produced letters to Iran's supreme leader by Maduro's foreign minister and a diplomatic note from Iran's Embassy in Caracas backing their claim.

But prosecutors have cast doubt on the authenticity of those documents and point out that the State Department has never accepted Saab's supposed status as diplomat. Indeed, in 2019, the U.S. recognized opposition leader Juan Guaidó as Venezuela's legitimate leader, although more recently the Biden administration has taken steps to engage with Maduro, who has clung to power in the face of severe U.S. oil sanctions.

"This is a ruse set up by a rogue nation to evade criminal prosecution," Jeremy Sanders, an attorney with the Justice Department in Washington, said during a hearing last month.

Attorneys for Saab did not comment on the ruling.

U.S. officials maintain Saab was among a cohort of insiders who reaped huge windfall profits from dodgy contracts to import food while millions in the South American nation starved. He was indicted in Miami in 2019 on money laundering charges connected to an alleged bribery scheme that pocketed more than $350 million from a low-income housing project for the Venezuelan government.

Maduro's officials consider Saab a "kidnapping" victim and have tried to rally popular support in Venezuela to demand his freedom. At the time of his arrest, they said he was on a humanitarian mission to Iran to negotiate the purchase of food, which has become more difficult to import as U.S. sanctions have cut off Venezuela's ties to the western financial system, exacerbating an economic collapse marked by years of hyperinflation, electricity blackouts and widespread shortages.

Maduro led supporters to chants of "Free Alex Saab" at a rally Sunday in Caracas to commemorate May Day.

But it's not clear Saab remained loyal to the government that made him rich.

Recently unsealed court records show that in the years prior to his arrest Saab had been an "active law enforcement source" helping agents from the Drug Enforcement Administration and Federal Bureau of Investigation investigate allegations of bribery of top Venezuelan officials. As part of that cooperation, he also agreed to surrender profits obtained as part of the dirty dealings.

In an April 2019 meeting with U.S. prosecutors in Europe, the two sides discussed having Saab surrender on May 30 of that year, according to a summary of events contained in court records. But the deadline passed and Saab never showed up, having ended all communication with U.S. officials, according to the court record. He was indicted a few weeks later.

Joshua Goodman reports for the Associated Press.

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