Japanese automaker Mitsubishi's (7211.T) subsidiary in Venezuela has halted operations due to a delay in the import of parts for assembly, a union official said on Friday.

Like other private businesses in the South American nation, carmakers have been complaining that the socialist government's complicated currency controls and bureaucratic processes are slowing imports of essential products.

Mitsubishi's local unit, MMC Automotriz, began a month-long stoppage on Monday, union official Jahaziel Bolivar told Reuters. "We're waiting for materials to arrive," he said, adding that they were held up at a port in western Venezuela.

Automobiles are just one sector of many where President Nicolas Maduro's government is facing clamor to release more dollars and ease the bureaucratic process for imports. He says unscrupulous businessmen exaggerate needs in order to flip dollars on the black market for profit.

Car production in 2014 has fallen 83 percent year-on-year, with just 8,508 vehicles produced, compared with 50,967 in the same period last year.

The auto industry says it is owed $1.9 billion in dollar liquidations from the state currency board. Various plants have had stoppages or are operating at minimum capacity.