Released at the UN climate summit in Brazil, the analysis found Azerbaijan and Kazakhstan were by far the largest suppliers of crude, accounting for 70 percent of shipments between November 1, 2023 and October 1, 2025.

Russia, Greece and the United States were the top providers of refined petroleum products -- with the US standing out as the sole supplier of JP-8, a jet-fuel blend designed for military aircraft.

"The states that have supplied Israel with fuel during this period have done so in full knowledge of its atrocities," said Oil Change International, which advocates for a global phase-out of fossil fuels.

"Their complicity is documented here to hold these states accountable. These states must address their role in the genocide and cease their complicity."

The group commissioned research firm Data Desk to conduct the analysis, which tracked 323 shipments during the study period, totaling 21.2 million tonnes.

The conflict began in October 2023 when an attack by Islamist group Hamas killed 1,221 people in Israel, mostly civilians, according to an AFP tally based on official figures.

Israel's retaliatory campaign has since killed more than 69,000 Palestinians, according to Gaza's health ministry, whose data is deemed reliable by the United Nations.

Israel and Hamas agreed to a ceasefire in Gaza that has largely halted the war since October 10, though violent incidents continue to be reported, often with fatalities.

The International Court of Justice has ruled that Israel's actions are unlawful, and a UN Commission has concluded Israel has committed genocide in Gaza.

Irene Pietropaoli, a senior fellow in business and human rights at the British Institute of International and Comparative Law, said states were obliged to follow the ICJ's interim order directing them to "prevent and punish genocide."

"States must consider that their military or other assistance to Israel's military operations in Gaza may put them at risk of being complicit in genocide under the Genocide Convention," she said.

In August 2024, Colombian President Gustavo Petro announced that Colombia had formally suspended coal exports to Israel.

While official data indicates Brazil last sent oil directly to Israel in March 2024, the head of the Rio de Janeiro Oil Workers Union has claimed Brazil may have rerouted shipments via Italy.