He suggested that getting countries to volunteer unarmed military observers for a residual United Nations force in the enclave would now be more difficult.
The gunmen waited until the first armored personnel carrier had crossed their path, choosing instead to fire at the unarmed observers.
Around the same time, the bodies of two unarmed military observers, stationed in a gold mining area called Mongbwalu, north of here, were found.
The unarmed observers, caught in the middle, could do little.
Resolution 2043 authorises up to 300 unarmed military observers, plus an appropriate civilian component.
Of the United Nations personnel, 680 will be armed infantry whose mission is to defend the unarmed observers who are to enforce the cease-fire.
The United Nations also said that three unarmed military observers and their translator were killed in Tajikistan this month.
In every patrol there are 2 vehicles with 4 unarmed military observers and one interpreter.
According to the part of the arrangement finally agreed to this morning, the unarmed observers will maintain positions only if fighting stops.
And as an unarmed observer, he could do nothing but watch and take photographs.