While many observers have praised Mexico’s move to privatize its energy sector, not everyone has embraced the changes.

Tens of thousands of protesters turned out in Mexico City to oppose the 2013 constitutional amendment that opened the doors for private investors to develop Mexico’s oil and gas resources for the first time in 75 years, the BBC reported at the time.

In recent months President Enrique Peña Nieto has faced opposition to financial reforms and his handling of the disappearance of dozens of students in September.

The administration has an uphill battle to convince its critics that the energy reform process is legitimate. Mexico Undersecretary of Hydrocarbons María de Lourdes Melgar Palacios said that is a main objective in developing new energy regulations to augment energy laws passed this summer.

“We are doing everything through a bidding processes,” she said at an event at the Woodrow Wilson center last month. “In this regard, we establish a mechanism for checks and balances.”

David Goldwyn, an energy fellow at the Atlantic Council and former State Department counsel for international energy affairs, praised the efforts, which he equated to building a plane while flying it.

“The team in Mexico has not only passed but shattered expectations,” he said.

While opposition may be outspoken, the political means to roll back the revisions are unlikely, according to former Mexico Energy Secretary Jordy Herrera who asserted that the left-wing protesters seen in the streets do not represent the feelings of most of the nation.

“We are pretty convinced that this is the right path,” he said. “Mexico is a different country now.”