WASHINGTON - The Biden administration will "calibrate" its sanctions policy towards Venezuela depending on how the high-stakes election unfolds in the OPEC nation on Sunday, U.S. officials said, signaling that Washington could ease punitive measures if President Nicolas Maduro holds a fair vote.

But Washington also put Maduro on notice that if he claims victory without providing proof, it would "call into question" whether the international community should accept the outcome.

Maduro is seeking his third term as leader of Venezuela, which is under heavy U.S. sanctions. His challenger, opposition candidate Edmundo Gonzalez, has attracted significant support.

The opposition and some independent observers have questioned whether the vote will be fair, saying decisions by electoral authorities and the arrests of some opposition campaign staff are meant to create obstacles.

Senior U.S. officials said on Friday they were closely watching the final lead-up to the election. Washington relaxed but then reinstated sanctions on Venezuela's vital oil industry in recent months after it said Maduro's government failed to comply with an electoral deal guaranteeing an inclusive democratic vote.

The officials, briefing reporters on condition of anonymity, said they would not prejudge the outcome, but expressed concern about possible political repression. They also warned Venezuela's military, which has long supported Maduro, not to "put its thumb on the scale" by interfering in the process.

"The United States is prepared to calibrate our sanctions policy vis a vis events as they may unfold in Venezuela," one U.S. official said. "As we look at the post-electoral period, we will continue to evaluate and update our sanctions policy as required based on our foreign policy goals."

The officials declined to specify what actions might be under consideration.

INTERNATIONAL OBSERVERS

One official said it was "deeply concerning" that Maduro's government had limited the number of international observers.

The official specifically urged Venezuelan authorities to reconsider a decision to bar a plane carrying regional ex-presidents from flying from Panama to Caracas, saying their presence was needed to provide assurances the election "will be representative of the will of Venezuelan voters."

Gonzalez, a veteran former diplomat, inherited the opposition mantle from Maria Corina Machado, who enjoys wide popularity and won the opposition primary but was barred from holding public office.

Maduro, a Socialist whose 2018 reelection was rejected by most Western governments as a sham, has said Venezuela has the world's most transparent electoral system.

Maduro has presided over an economic collapse, the migration of about a third of the population, and a sharp deterioration in diplomatic relations, crowned by sanctions that have crippled an already-struggling oil industry.

Gonzalez, 74, is known for his calm demeanor and his promises that change could bring home many migrants.

Analysts have suggested that a Maduro reelection or post-election upheaval could spur more Venezuelans to leave the country and head for the U.S.-Mexico border.

With immigration already a hot-button issue in the U.S. presidential campaign, that could create new problems for Vice President Kamala Harris, who is seen as the likely Democratic nominee after President Joe Biden ended his reelection bid on Sunday.

  - Reuters