"Since nothing sufficient has happened at this stage we have already put two units of the armed forces of Congo on notice that if they do not act promptly we shall cease supporting them, " a UN official in New York said on condition of anonymity.

BBC: UN in DR Congo 'army rape' ultimatum

The plan says that "each party shall maintain a national system for responding promptly and effectively to oil pollution incidents" without requiring any clear details on the number of ships or personnel that would be needed to cope with a spillage.

BBC: Concerns raised over 'useless' Arctic oil spill plan