The left-winger, a former mayor of Mexico City, ran under a three-party coalition led by the leftist National Regeneration party, which he founded in 2014.

Early results following Sunday’s election indicated that López Obrador was set to win at least 53% of the vote. This would be the largest margin victory in a Mexican presidential election since the 1980s.

Speaking late on Sunday after the polls closed, he said that corruption was “the result of a decadent political regime”.

“We are absolutely convinced that this evil is the main cause of social and economic inequality, and also that corruption is to blame for the violence in our country.”

He repeated his campaign pledge to review energy contracts issued to companies by the outgoing administration for corrupt practices.

He warned that any anomalies would be addressed by the Mexican Congress and taken to national and international tribunals.

He also vowed to double pensions for the elderly when he takes office on 1 December, in a move to reduce Mexico’s disparate income levels.

López Obrador said he was “not looking to construct a dictatorship, either open or hidden.”

He also said he would work to improve the relationship with the US.

The relationship between the two neighbouring countries has been strained since the election of Donald Trump as president who has criticised Mexico over trade and migration.