Morocco on Saturday decried "provocative" acts and "transgressions" at the opening of a regional football tournament in Algeria, a new episode in an ongoing political crisis between the North African neighbours.
Morocco and Algeria are locked in a bitter rivalry partly over the disputed territory of Western Sahara, where the Algerian-backed Polisario movement seeks an independence referendum.
Morocco's football federation in a statement slammed a "provocative and surreal speech" at the African Nations Championship (CHAN) opening ceremony on Friday in which the grandson of Nelson Mandela called to "free" the disputed territory.
Rabat sees Western Sahara as an integral part of the kingdom and a highly sensitive issue of security and national pride.
"Let us fight to free Western Sahara from oppression," Mandla Mandela told the crowd at the stadium named in honour of his grandfather, South Africa's first democratically elected president after the fall of apartheid, in the Algerian city of Constantine.
"Don't forget the last colony of Africa, Western Sahara," he added.
The desert territory boasts rich Atlantic fisheries, phosphate resources and a land route to markets in West Africa.
The Moroccan federation said the speech "flouted the rules governing the organisation of football events under the auspices of the Confederation of African Football (CAF)".
The Moroccan federation also decried "racist" anti-Moroccan remarks at the opening ceremony, as videos circulated on social media appearing to show Algeria supporters chanting derogatory slogans against Moroccans.
The federation said it had written to the CAF to ask it to uphold "all its responsibilities in the face of these flagrant transgressions that have no relation to the principles and values" of football.
The United States in 2020 recognised Moroccan sovereignty over the Western Sahara in a quid pro quo for re-establishing ties with Israel, to the chagrin of Algiers -- which for decades has seen itself as North Africa's main champion of the Palestinian cause.
"We stand to together to fight for the liberation of Palestine," Mandela also said in his speech.
Morocco on Friday decided not to send its under-23 team to the CHAN tournament after Algeria refused to authorise a direct flight from Rabat.
Algeria broke off diplomatic ties with Morocco in August 2021 and closed its airspace to all Moroccan flights the following month.
CHAN organisers said the team could have taken an indirect flight.
Morocco made history in December by becoming the first African or Arab team ever to reach the semi-finals of a World Cup.
Morocco's Atlas Lions' under-23 team won the last two CHAN tournaments.