Hugo Chavez (file photo)

The State Department said Wednesday the United States had no part in a decision by three Venezuelan opposition parties to withdraw from congressional elections on Sunday. Venezuelan President Hugo Chavez alleges the pull-out is part of a U.S. destabilization effort.

The State Department says the United States was not involved in the decision by the Venezuelan parties to pull out of the election race, but does say it shares concerns in the country about the fairness of the electoral process.

The three parties, including two which played leading roles in the country's governance before Mr. Chavez took office in 1998, announced their decision to drop out of the election on Tuesday. They cited concerns about errors in the official voter registry and the reliability of electronic voting machines.

The move drew immediate criticism from Mr. Chavez, who called it an act of political sabotage aimed at discrediting his government. He also said the United States had encouraged the pullout, which he depicted as the start of a U.S. destabilization effort.

The denial of U.S. involvement came from State Department Spokesman Sean McCormack.

He said the three parties acted on their own because of a lack of confidence in the Venezuelan electoral system's transparency, and ability to guarantee the secrecy of the vote, and he said other parties also have misgivings:

"Some parties have decided to remain in the race while other parties have yet to announce a final decision on participation. Venezuelans like all people have a right to free and fair elections. We are concerned that this right is increasingly in jeopardy and we will continue to support the Venezuelan peoples' effort to advance transparent electoral processes and safeguard their basic political and civil rights," he said.

The partial opposition pullout is expected to allow Mr. Chavez' leftist party to strengthen its control of the national assembly.

The United States has been a critic of what it sees as Mr. Chavez' increasingly heavy handed rule, and association with Cuba's President Fidel Castro.

Mr. Chavez in turn, despite U.S. denials, has accused Washington of having backed the military coup that briefly drove him from office in 2002, and of bankrolling the unsuccessful recall campaign against him last year.

The tension in relations was reflected in an incident earlier this week, when a U.S. Congressional delegation decided to leave the Caracas airport for home after having been refused permission to disembark in a 90-minute standoff.

Spokesman McCormack said Wednesday the Venezuelan government had apologized for the incident, though Venezuelan officials said the legislators had not been denied entry and there had been no apology.