The US has vetoed a draft United Nations Security Council resolution that demanded an “immediate, unconditional and permanent ceasefire” between Israel and Hamas in Gaza.

The resolution also called for unhindered aid access across the war-torn enclave.

Reuters reported 14 other countries on the council voted in favor of the draft, as a humanitarian crisis grips the area, where famine looms and aid has only trickled in since Israel lifted an 11-week blockade last month.

The US is Israel’s biggest ally and arms supplier and said it would not support any measure that fails to condemn Hamas and does not call for the group to disarm and leave Gaza.

Acting U.S. Ambassador to the U.N. Dorothy Shea told the council before the vote it would also undermine U.S.-led efforts to broker a ceasefire.