Venezuela is postponing bidding among foreign oil companies for contracts to exploit seven areas within its heavy-oil-producing Orinoco belt.
Oil Minister Rafael Ramirez says Venezuela has decided to suspend bidding because "the companies need more time for their analysis."
Bidding was expected to begin on July 28.
Ramirez did not offer a new timetable for the process during a visit to the Orinoco belt on Monday.
Faced with cash flow problems, Venezuela decided last year to invite foreign oil companies to consider taking minority stakes in seven projects run by state oil company Petroleos de Venezuela.
The Orinoco belt is expected to pump 400,000 barrels of crude per day by 2011 and double that output by 2015.