New Delhi, May 15 -- Nickolay Mladenov, the top diplomat overseeing the U.S.-brokered ceasefire in Gaza, on Wednesday acknowledged that the truce was stalled, saying the deadlock over disarming Hamas had paralyzed reconstruction of the war-battered territory.

Mladenov expressed frustration with the status quo that has emerged since the ceasefire was reached last October and said his office is addressing violations by both sides on a daily basis. But he repeatedly cited the disarmament issue as a central sticking point, saying Hamas' obligation to give up its arsenal is "not negotiable" and that progress on all other issues - including reconstruction, Israeli troop withdrawals and the establishment of a new Palestinian government - was be...