United Nations, Dec 9 : The US has vetoed a UN Security Council resolution demanding immediate humanitarian ceasefire in Gaza. The resolution, drafted by the UAE and backed by more than 100 countries, gained support from 13 of the 15 Security Council members, with Britain abstaining on Friday. UN Secretary-General Antonio Guterres had invoked Article 99 of the UN Charter to urge the organisation's most powerful body to call for a ceasefire, Xinhua news agency reported. Article 99 states, "The Secretary General may bring to the attention of the Security Council any matter which in his opinion may threaten the maintenance of international peace and security." The text of the resolution called for an immediate halt of fighting between Hamas and Israel, and the protection of both Israeli and Palestinian civilians under international humanitarian law. It also demanded the "immediate and unconditional release of all hostages". Palestine's ambassador to the United Nations, Riyad Mansour, told the council that the result of the vote was "disastrous," adding: "Millions of Palestinian lives hang in the balance. Every single one of them is sacred, worth saving." He said that it was "beyond regrettable" that the Security Council was hindered from fulfilling its duties -- via a newly adopted resolution -- amid the crisis. Rather than enabling the council to execute its charge by at least issuing a definitive appeal, after two months of mass killings and atrocities, "the war criminals are given more time to perpetrate their crimes," Mansour added. "How can this be justified? How can anyone justify the slaughter of an entire people?" he said. /IANS