MEXICO CITY (AP) ― President Enrique Pena Nieto announced the construction of a new international airport for Mexico City on Tuesday, saying it will quadruple the capacity of the current one.

Costing an estimated $9.2 billion, the facility will have six runways and a capacity of 120 million passengers a year. Pena Nieto said it has been clear for decades that the capital’s overtaxed airport needed to be replaced.

“The current saturation restricts travel between the different states of the country, limits Mexico’s connectivity to the world, slows investment and commerce,” he said. “We can no longer keep postponing the fundamental solution.”

More than a decade ago, protests led authorities to scrap a planned new airport on the outskirts of Mexico City. The new proposal is to build on federally owned land next to the existing facility.

Pena Nieto said it will be Mexico’s largest public infrastructure project in recent years, and called it “Mexico’s gateway to the world.”

He made the announcement during his second state-of-the-nation address, in which he defended reforms instituted since he took office in 2012. He predicted a brighter economic future, while acknowledging that recent performance has disappointed.

Independent analysts have lowered their 2014 economic growth forecast from 2.56 percent to 2.47 percent. GDP expanded just 1.1. percent the previous year.

“It’s clear that we still have not arrived at the economic growth rates that the country and its people need,” Pena Nieto said. “The challenge of growth is not new for Mexico; achieving an accelerated, sustained and sustainable growth has been our principal economic challenge for decades.”

Pena Nieto’s administration has been waging a campaign to promote his reforms amid declining public support for the government.

A recent poll by Pew Research found that Pena Nieto’s approval numbers fell six points from last year, to 51 percent. Survey respondents with a negative view of his leadership rose nine points to 47 percent. Sixty percent said they were dissatisfied with the economy and Pena Nieto’s handling of it.

The Pew survey relied on in-person interviews with 1,000 people and had a margin of error of 4 percentage points.

Jose Antonio Crespo, a professor at Mexico’s Center for Economic Research and Teaching, said Pena Nieto faces a tough challenge on issues such as the economy, corruption and public insecurity. Although government figures show crime falling, many Mexicans consider it to still be one of the country’s most serious problems.

“The problem is that with great corruption, all that is positive can be distorted ― the energy and communications reforms,” Crespo told The Associated Press. “As long as that corruption is there, in reality I don’t think the country can truly change or advance significantly.”