The UN adopted a resolution over the weekend on the "protection of civilians and upholding legal and humanitarian obligations" in relation to the ongoing Gaza crisis.
The vote passed with 120 nations, including New Zealand and Solomon Islands voting in favour. However, the majority of Pacific states voted against - siding with the United States, Israel and United Kingdom.
Israel argued that any ceasefire would give Hamas time to rearm and attack Israel again, following the massacre of at least 1400 Israeli citizens - most of them civilians - on 7 October. More than 220 were taken hostage.
Israeli forces are waging ground operations against Hamas in Gaza as Israeli Prime Minister Benjamin Netanyahu aims to crush the Palestinian militant group.
The Gaza Health Ministry said the death toll among Palestinians passed 8000, mostly women and children, and more than than 1.4 million people in Gaza had fled their homes.
Fiji, Marshall Islands, Federated States of Micronesia (FSM), Papua New Guinea, Nauru and Tonga voted against a UN resolution. While Australia, Kiribati, Palau, Tuvalu and Vanuatu abstained. Samoa remained silent.
Bainimarama criticised Fiji Prime Minister Sitiveni Rabuka for being "contradictory" and said the vote by Fiji on the world stage "did not reflect the view of most Fijians", which was a call for a ceasefire, he told RNZ Pacific on Monday.
"Stop the suffering right now. Stop the killing. Allow humanitarian aid. That is what is required in the resolution," Bainimarama told RNZ Pacific.
Earlier this month, Rabuka self-proclaimed he was "an apostle for peace" and had proposed the Pacific be a conflict free-peace zone.
Rabuka plans to discuss his peace-zone proposal at the 52nd Pacific Islands Forum Leaders Meeting in the Cook Islands next month.
However, Bainimarama said Fiji's stance at the UN was not one of peace and instead "put their troops which are stationed in Iraq, at risk".
The FijiFirst leader said he did not support either side of the conflict but did support "a resolution" to save thousands of innocent people, including women and children, many of whom have lost everything.
"This vote goes against the fundamental principles of humanity, peace, and justice that should guide the nation's international policies," he said.
"Fiji's vote at the United Nations in favour of war contradicts the nation's long-standing legacy as peacekeepers, a legacy upon which both our reputation and that of the Republic of Fiji Military Forces have been founded.
"We have troops in the Middle East, in Iraq, Syria... all over the Middle East. That is a concern for us. Parents of the troops are worried about what will Hamas do to them in the Middle East. That is the other thing we should be worried about."