TEXCOCO, Mexico (Reuters) - Mexican presidential front-runner Andres Manuel Lopez Obrador said on Sunday that if he wins the July 1 election, he will aim to hold a public vote before taking office on whether to finish building a $13 billion airport outside Mexico City.

Mexico's presidential front-runner Andres Manuel Lopez Obrador of the National Regeneration Movement (MORENA) greets supporters in Oaxaca, Mexico June 16, 2018. REUTERS/Jorge Luis Plata

The airport, spearheaded by President Enrique Pena Nieto and set to be half-completed by year’s end, has come under fire by Lopez Obrador for being too expensive and allegedly generating corruption.

Lopez Obrador, who leads by wide margins in all major opinion polls, has proposed “public consultations” for various issues including changes to a sweeping energy reform and even his performance as president, but has given few details of how they would work.

He said that if elected, he would seek a meeting with Pena Nieto on July 3 to discuss the airport, but did not say how he would hold a public consultation as president-elect.

It would appear he would require the outgoing president’s approval for such an initiative.

Pena Nieto’s office did not respond to a request for comment.

Pena Nieto previously said he would not halt airport construction while his administration completes its term.

Lopez Obrador said the vote on the Norman Foster-designed airport, Mexico’s biggest infrastructure project, would be conducted by the National Electoral Institute (INE), which runs elections, or a citizen committee.

“It could be the INE or a committee of independent citizens of unobjectionable honesty,” he told reporters after a campaign event in the city of Texcoco in Mexico State, where the airport is being built.

“We can resolve this, at the latest, in two months. ... Perhaps in the first two weeks of September ... it can’t wait any longer,” he said.

The next president takes office in December. Pena Nieto is constitutionally barred from seeking another term.

Lopez Obrador initially vowed to scrap construction of the airport and instead add runways at a smaller facility to handle Mexico’s increasing air travel demands, setting business leaders’ nerves on edge.

The airport authority said a cancellation would cost some $6.6 billion, and Mexican billionaire Carlos Slim, whose companies are co-designing, co-building and co-financing the project, also spoke out in its defense.

Lopez Obrador said later he would review the billions of dollars in airport construction contracts and possibly offer a private-sector concession.

All of those options would be up for a public debate, he said on Sunday.

“We’re constructing a true democracy, not a dictatorship, and it will be like this in all cases,” he said. “We’re going to listen to the people, and the people will be in charge, always.”