Thirteen Security Council members voted in favour of a brief draft resolution, put forward by the United Arab Emirates, while Britain abstained.
The vote came after UN Secretary-General Antonio Guterres made a rare move on Wednesday to formally warn the 15-member council of a global threat from the two-month long war.
"It's not an issue about isolation. It's an issue about what we think is best to try to end this conflict as soon as possible and also to help facilitate more humanitarian assistance going into Gaza," Deputy US Ambassador to the UN Robert Wood told reporters ahead of the vote.
"We can't just snap our fingers and the conflict stops. This is a very, very difficult situation," he said.
The United States has vetoed a UN Security Council demand for an immediate humanitarian ceasefire. (EPA PHOTO)
The US and Israel oppose a ceasefire because they believe it would only benefit Hamas. Washington instead supports pauses in fighting to protect civilians and allow the release of hostages taken by Hamas in a deadly October 7 attack on Israel.
A seven-day pause, that saw Hamas release some hostages and an increase in humanitarian aid to Gaza, ended on December 1.
After several failed attempts to take action, the Security Council last month called for pauses in fighting to allow aid access to Gaza, which Guterres on Friday described as a "spiralling humanitarian nightmare".
The US favours its own diplomacy, rather than Security Council action, to win the release of more hostages and press Israel to better protect civilians in Gaza as it retaliates for the Hamas attack that Israel says killed 1200 people.
However, US Secretary of State Antony Blinken acknowledged on Thursday that there was a "gap" between Israel's intent to protect civilians and what has happened on the ground. Gaza's Health Ministry says more than 17,480 people have been killed.
"The eyes of the world – and the eyes of history – are watching. Time to act." — UN Web TV (@UNWebTV) @antonioguterresWatch Security Council on the situation in the Middle East, including the Palestinian question: https://t.co/XaSTmxOwNxAvailable in: لعربية 中文 English Français Русский Español pic.twitter.com/RGjtKLKrRyDecember 8, 2023
Israel has bombarded Gaza from the air, imposed a siege and launched a ground offensive. The vast majority of the Palestinian enclave's 2.3 million people have been driven from their homes.
"There is no effective protection of civilians," Guterres told the council earlier on Friday. "The people of Gaza are being told to move like human pinballs - ricocheting between ever-smaller slivers of the south, without any of the basics for survival. But nowhere in Gaza is safe."
In Washington, Jordan's Foreign Minister Ayman Safadi told reporters earlier on Friday that if the Security Council failed to adopt the resolution, "it is giving Israel a license to continue with its massacre of Palestinians in Gaza".
Along with demanding an immediate humanitarian ceasefire, the draft text said Palestinian and Israeli civilian populations must be protected and demanded the immediate and unconditional release of all hostages.
Israel's UN Ambassador Gilad Erdan told the Security Council earlier on Friday that there was a ceasefire that had been broken by Hamas on October 7.
"The irony is that regional stability and the security of both Israelis and Gazans can only be achieved once Hamas is eliminated, not one minute before," Erdan said. "So the true path to ensure peace is only through supporting Israel's mission - absolutely not to call for a ceasefire."
