The US decision to recognise Morocco's claim over the disputed Western Sahara region has angered the territory's Polisario Front, whose spokesman told BBC Focus on Africa it was a "dangerous setback".
"Sovereignty over Western Sahara is a decision that should be taken exclusively by the Saharawi people through a genuine expression of their will," said spokesman Oubi Bouchraya Bachi, adding "it doesn’t belong to the US" or any other power.
Western Sahara was annexed by Morocco in 1975. A 16-year-long insurgency ended with a UN-brokered truce in 1991 and the promise of a referendum on independence, which has yet to take place.
The Polisario Front is a nationalist group backed by Algeria which has been seeking to establish an independent state - a claim recognised by the African Union.
The announcement by outgoing US President Donald Trump comes weeks after hostilities between Moroccan and Polisario forces resumed, breaking almost three decades of ceasefire.
The deal is part of a wider agreement between the US and Morocco that sees it normalise relations with Israel.
"We have been warning that importing the Middle East dynamic to North Africa will engender a lot of instability," Mr Bachi said of the US-Morocco pact.
"We are very hopeful the new administration [in the US] will take a different step," he added.