A diplomatic row has broken out between Mexico and Spain after the Mexican president wrote to King Felipe VI demanding he apologise for crimes committed against Mexico’s indigenous people during the conquest 500 years ago.

In a video filmed at the ruins of the indigenous city of Comalcalco, in southern Mexico, Andrés Manuel López Obrador called on Spain and the Vatican to recognise the rights violations committed during the conquest, led by Hernán Cortés. The video was posted on the president’s social media accounts.

“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 [indigenous] temples,” he said. “The time has come to reconcile. But let us ask forgiveness first.”

The remarks came two months after the Spanish prime minister, Pedro Sánchez, made an official visit to Mexico; his government reacted angrily to López Obrador’s letter.

“The Spanish government profoundly regrets the publication of the Mexican president’s letter to his majesty the king on 1 March and completely reject its content,” a government statement read.

“The arrival of the Spanish on Mexican soil 500 years ago cannot be judged in the light of contemporary considerations. Our closely related peoples have always known how to view our shared history without anger and from a shared perspective, as free peoples with a common heritage and an extraordinary future.”

Reaction in Spain split across political lines. Albert Rivera, the leader of the centre-right Citizens party, said the letter “was an intolerable offence to the Spanish people”, while Ione Belarra, from the leftwing Podemos party, said López Obrador “has every right to ask the king to apologise for the abuses of la conquista”.

Pablo Casado, leader of the conservative People’s party: “It’s scandalous ignorance and a real affront to Spain and its history.”

Harim Gutiérrez, a professor at the Metropolitan Autonomous University in Mexico City, said López Obrador’s letter was an example of “the instrumentalisation of history for political purposes”.

“He [López Obrador] says it’s an attempt at … achieving ‘a general agreement’ based on forgiveness, which is consistent with his policies of ‘peace and love’,” Gutiérrez added. “The governments of independent Mexico have had all this time to try to overcome the wrongs of Spanish domination and, currently, in Mexico, the legacy of Spanish domination doesn’t explain all our difficulties.”

López Obrador took office on 1 December vowing to champion Mexico’s poor and indigenous people. Unlike millions of mixed-race Mexicans – mestizos – the president is almost entirely of Spanish descent, whose grandparents emigrated from Asturias and Cantabria in northern Spain.

Cortés led a small squadron of soldiers – equipped with horses, armed with diseases such as smallpox, and abetted by indigenous groups at odds with the Aztecs – to Mexico City (then known as Tenochtitlán) in 1519.

The Spanish sacked the city two years later and proceeded to convert the indigenous populations to Catholicism. Cortés has long occupied a controversial place in Mexican history. His indigenous mistress, La Malinche, is still seen as a traitorous figure – with her name forming the epithet malinchista, someone who prefers the foreign to the domestic.

In 2021, there are plans to mark the 500th anniversary of the fall of Tenochtitlán and 200 years since Mexico gained its independence from Spain. López Obrador says there must first be reconciliation before these events can be commemorated.

Spain has shown little contrition about its colonial past. Last November, Pablo Casado, the leader of the rightwing Popular party, commented that: “We didn’t colonise, what we did was to make Spain larger.”

In recent years, various other countries have faced up to the crimes committed against indigenous people during colonisation.

In 2008, the Australian parliament offered a formal apology to indigenous Australians. “We apologise for the laws and policies of successive parliaments and governments that have inflicted profound grief, suffering and loss on these our fellow Australians,” the parliament said. “We apologise especially for the removal of Aboriginal and Torres Strait Islander children from their families, their communities and their country.”

The Canadian prime minister, Justin Trudeau, has apologised on several occasions to indigenous Canadians.

In the US, an apology to Native Americans buried in the middle of a defence appropriations spending bill in 2009 called on the then president Barack Obama “to acknowledge the wrongs of the United States against Indian tribes in order to bring healing to this land”, something that Obama never did.

In 1995, Queen Elizabeth II formally apologised for atrocities committed against the Maori Tainui tribe in New Zealand in 1865, and in 2013 the British government expressed “sincere regret” for torture and abuse committed by British colonial officers against Kenyans in the 1950s.

Pope Francis, speaking in Bolivia in 2015, asked for forgiveness “for crimes committed against native peoples during the so-called conquest of America”.