Oilfield services provider Schlumberger Ltd said it would reduce its operations in Venezuela due to payment problems, a further sign of the cash crunch facing the OPEC nation because of weak oil markets.

Venezuelan state oil company PDVSA, the exclusive operator of the country’s oilfields, has built up billions of dollars in unpaid bills to service providers as a result of cash-flow problems.

“Schlumberger appreciates the efforts of its main customer in the country to find alternative payment solutions and remains fully committed to supporting the Venezuelan exploration and production industry,” the company said in a statement.

“However, Schlumberger is unable to increase its accounts receivable balances beyond their current level.”

The company said the reduction will take place through this month, allowing for a safe wind-down of operations.

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