Spain's government has refused a demand from Mexico's new president that it apologise for conquering the country five hundred years ago.

Firing the first shots in what threatens to become a diplomatic row, the Left-wing Mexican leader Andrés Manuel López Obrador announced on Monday that he had sent letters to Spain’s King Felipe VI and Pope Francis urging them to apologize for crimes committed against the indigenous peoples of what is today Mexico.

“There were massacres and oppression. The so-called conquest was waged with the sword and the cross. They built their churches on top of the temples,” Mr López Obrador said in a video message.

He filmed the clip at a Mayan monument near the site of the first battle in which Spanish conquistador Hernán Cortés fought indigenous people 500 years ago this month.

Starting from the Tabasco coast and assisted by some indigenous groups who threw in their lot with the invaders, Cortés led a squadron of soldiers eastwards to victory in Tenochtitlan - today’s Mexico City - two years later in 1521. The Aztec empire was destroyed and the indigenous populations were converted to Catholicism.

At a speech to supporters later on Monday, Mr López Obrador said he wanted to reconcile Mexico, the Spanish crown and the Vatican by “together reviewing the history of that military invasion and three centuries of colonisation”.