Morocco has said it is reducing its staff and support for the UN mission in Western Sahara, in protest at Secretary General Ban Ki-moon's recent comments about the disputed territory.
The government in Rabat has also threatened to pull its troops out of all UN peacekeeping operations.
The escalating dispute between Morocco and the UN was sparked when the UN chief visited Saharan refugee camps earlier this month.
Speaking after the visit, he referred to what he called Morocco's "occupation" of Western Sahara.
Rabat reacted with outrage, saying the UN chief had abandoned his "neutrality, objectivity and impartiality".
When a huge protest was mobilised in the Moroccan capital over his comments, it was Ban’s turn to be offended at the slogans.
Morocco has been administering the Western Sahara, which was formerly under Spanish colonial rule, since 1975. Rabat's official stance is that it is historically part of Morocco.
The territory's long-standing inhabitants are a culturally and ethnically distinct group. Under the Polisario Front from the mid-1970s, many of them have been seeking independent nationhood.
Polisario waged a guerrilla war until a UN-brokered ceasefire in 1991. But the two sides have been deadlocked since, particularly over a referendum on the territory's future.
A plan for regional autonomy proposed by Morocco has been rejected by Polisario as not enough.
Last week, Ban pledged to restart UN efforts to reach a solution.
But what effect will this dramatic diplomatic standoff have on a dispute that has proved so intractable for so long?
And is there any chance of a breakthrough?
Presenter: Kamahl Santamaria
Samir Bennis - Editor-in-chief, MoroccoWorldNews.com
Christos Tsatsoulis - Former UN peacekeeper and field commander in Western Sahara
Carne Ross - Executive director, Independent Diplomat consultancy
Source: Al Jazeera