Prime Minister John Key has blasted the international community for failing to end the brutal civil war in Syria.
Mr Key has chaired a fiery debate at the United Nations Security Council in New York, a few days after a fragile ceasefire between government and rebel forces collapsed.
He accused UN member states of not living up to their mandate, saying "Syria has become a by-word for failure".
US Secretary of State John Kerry said it was "a moment of truth for the world" and called for an immediate grounding of all fighter aircraft in Syria's combat zones in a bid to end the bloodshed.
Mr Kerry revealed to the Security Council that four aid workers were killed in an air strike on a medical facility overnight - saying only Syrian and Russian planes were in the sky.
He also rubbished Russia's claims another aid convoy was destroyed by a cargo fire.
"The damage to the convoy was the direct result of the cargo catching fire? The trucks, and the food and the medicine just spontaneously combusted. Anybody here believe that?" Mr Kerry said. "This is not a joke. We’re in serious business here."
Mr Kerry said there was widespread agreement that restoring the ceasefire was the only option, and called on Russia's President Vladimir Putin to step up.
"If we decide not to do what it takes to make this work, this cessation of hostilities, then make no mistake my friends, the next time we convene here, we’re going to be facing a Middle East with even more refugees, with more dead, with more displaced, with more extremists, and more suffering on an even greater scale. That is a certainty."
Mr Key said New Zealand had made its mark on the Security Council by calling the meeting.
"I think what we proved is that we used our time as Presidency to address the single biggest issue that we’re all facing now, and while you can say ok, there was a bit of venting and a bit of frustration from various interventions, what other place can they continue to have those discussions? Everyone can see the ceasefire is struggling, but on the other side of the coin we need the ceasefire to work and you just have to accept that every step along the way here there’s a need to hit the reset button and today was a bit of a chance to hit the reset button."