Algeria and Morocco share a nearly 2,000 km (1,242 miles) border, which has been a source of tension since independence from French colonial rule.

Diplomatic relations between the two countries are also frosty and the long-running dispute about Western Sahara, a sparsely-populated territory annexed by Morocco in 1975, has also strained relations.

Its indigenous Sahrawi people, led by the Polisario Front and with a government in exile in Algeria, mounted a 16-year-long insurgency that ended with a United Nations-brokered truce in 1991.

The extended map of Morocco, including the territory of Western Sahara, does not correspond to official cartography of the country as published by the UN.

Berkane had their shirts confiscated by customs officials on arrival in Algeria for the first leg of their Confederation Cup clash last April and refused to wear an alternative shirt.

USM Alger declined to take to the pitch in the second leg in Morocco.

The extended map has also caused issues in other sports, as Algeria withdrew from the Arab Youth Handball Championship last year because the Moroccan side were “wearing shirts with political connotations”.