MEXICO CITY (AFP) - Mexican billionaire Carlos Slim will pay for the reconstruction of the metro line built by his company that collapsed, leaving 26 dead, President Andres Manuel Lopez Obrador said on Wednesday (June 30).

Slim, one of the world's richest men, has rejected suggestions that the elevated section of track that came crashing down on May 3 had flaws in its original construction.

But he has agreed to fund the repairs and finish the work within 12 months, Lopez Obrador told reporters.

"He's going to take charge of the reconstruction of the entire section, ensuring that it has all the necessary safety and at no cost to the people," he said.

After a meeting on Tuesday with Lopez Obrador, Slim said his company Grupo Carso would begin work "as soon as possible."

He said that he was "convinced" that the original construction had no defects.

The preliminary results of an independent investigation by Norwegian engineering company DNV released on June 16 identified a number of deficiencies in the construction process.

They included "unfinished and/or poorly executed welding," insufficient bolts and the use of different types of concrete, according to the report, which was commissioned by the Mexico City authorities.

Slim and his family, who control mobile telecom giant America Movil, are worth around US$70 billion (S$94 billion), according to Forbes magazine, making him Latin America's richest man.