Mexico City's airport, the country's busiest, may undergo a 5,000-hectare (12,350-acre) expansion to alleviate its severe congestion problems, Transportation Secretary Gerardo Ruiz Esparza said.

The proposal for the Benito Juarez International Airport was submitted to the government by "specialized companies" and will be analyzed over the next six months, he told the media.

The goal will be to examine the feasibility of the project and its approximate cost, according to Ruiz Esparza, who said the proposed expansion would occur on federally owned property.

"There'll be no need to acquire additional land, since we have sufficient land there to expand the airport's operational capacity," the secretary added.

Authorities will need to study issues pertaining to airspace, soil mechanics and hydraulics, as well as the relationship between the existing airport and the expansion project, he said.

"These are long-maturing projects and there can be no mistake made in their execution, so we'll have to wait," Ruiz Esparza added.

Flight schedules at the 60-year-old Mexico City International Airport were altered by official decree in July to bolster operational security and ease flight congestion during peak hours.

The airport was remodeled and expanded with the addition of Terminal 2 in 2007, five years after a plan to build a new airport in the nearby town of Texcoco was scrapped due to violent opposition from local landowners. EFE