Every couple of minutes, a large truck splattered with mud rumbles through the gate to what was once an expanse of mangroves. After recent rains, a lake has formed where the lush vegetation once flourished. Further on, more than 20  yellow diggers are hard at work scooping up sludge, which lorries dump in a nearby field.  For Mexican president Andres Manuel Lopez Obrador, who wants to turn this swamp into his signature infrastructure project – an $8bn oil refinery –  the location in his southeastern home state of Tabasco could not be better. The town is called Paraiso, or paradise.

The president sees it as the promised land for Pemex, the struggling national oil company; for Tabasco, whose economy shrank 11 percent in the first quarter; and for people like Concepcion Alvarez, who has parked his cart selling juices and snacks outside the gates  to the site. “This is going to change things. It’s going to create jobs,” he says.

The planned refinery, beside the Dos Bocas port, is much more than just a prestige project. It is a powerful symbol of the new economy Mr Lopez Obrador wants to build: state-directed, centrally-driven, reliant on national production and free of foreign influence.

Pemex is the centrepiece of Mr Lopez Obrador’s aspiration to overturn what he sees as more than three decades of “neoliberal” economic policy. One of his first moves after taking office was to order the oil company to add the motto “For the recovery of sovereignty” to its Mexican-eagle logo.