MEXICO CITY, July 1 (Reuters) - The first big set of contracts for oil and gas development in Mexico are likely to be delayed a few months, an energy ministry official said on Tuesday, after disagreements in Congress over detailed legislation to underpin them.
Congress is currently discussing so-called secondary laws, including some new rules and amendments to existing ones, needed to set in motion a landmark energy reform passed in December to open up the oil and gas industry to private capital.
Mexico's energy ministry initially said the first round of contracts, which will cover a mix of onshore and offshore fields including shale and deep water blocks, would come in the first half of 2015.
But disagreements between President Enrique Pena Nieto's centrist Institutional Revolutionary Party (PRI) and the opposition have pushed back deadlines for passing the rules.
"I think there will have to be a small adjustment in the times," said Gabriel Heller, the energy ministry's director of investments.
"I'd like to think we're talking about between the middle of next year to the end of the third quarter next year," he added, referring to when the first set of contracts will go to tender.
Ongoing congressional negotiations over the content of secondary laws for an overhaul of the telecommunications and broadcasting sectors have also affected the debate on the energy legislation, leading to further hold-ups.
The energy ministry has until mid-September to decide which fields will be assigned to Pemex in the so-called "Round Zero" allocation that will reveal which areas will then be up for grabs when competitive bid rounds begin. (Writing by Christine Murray; editing by Andrew Hay)