The Mexican Treasury's oil-related tax revenues rose to 763.81 billion pesos ($58.08 billion) in the January-August period, down 4.2 percent from the same period in 2012, the Finance Secretariat said.

Oil-related revenues include payments from state-owned oil giant Petroleos Mexicanos, or Pemex, the special gasoline tax, hydrocarbons rights and other petroleum revenues, the secretariat said in a report.

Revenues declined mainly as a result of the drop in the average price of Mexico's petroleum export blend, which averaged $100 per barrel in the January-August 2013 period, compared to the $104 per barrel registered during the same period last year.

The drop in the production of oil, which was off 0.60 percent, and natural gas, which fell 5.4 percent, as well as currency effects, also contributed to the decline in the Treasury's oil-related revenues during the period, the secretariat said.

Non-petroleum revenues rose 4.8 percent in the January-August period, thanks to increased enforcement, the secretariat said. EFE