The world’s top 100 oil and gas companies banked more than $30m every hour in unearned profit in the first month of the US-Israeli war in Iran, according to exclusive analysis for the Guardian. Saudi Aramco, Gazprom and ExxonMobil are among the biggest beneficiaries of the bonanza, meaning key opponents of climate action continue to prosper.

The conflict pushed the price of oil to an average of $100 (£74) a barrel in March, leading to estimated windfall war profits for the month of $23bn for the companies. Oil and gas supplies will take months to return to pre-war levels and the companies will make $234bn by the end of the year if the oil price continues to average $100. The analysis uses data from a leading intelligence provider, Rystad Energy, analysed by Global Witness.

The excess profits come from the pockets of ordinary people as they pay high prices to fill up their vehicles and power their homes, as well as from businesses incurring higher energy bills. Dozens of countries have cut fuel taxes to help struggling consumers, meaning those nations, including Australia, South Africa, Italy, Brazil and Zambia, are raising less money for public services.

Pressure is growing for windfall taxes on the war profits of oil and gas companies, with the European Commission considering a request from the finance ministers of Germany, Spain, Italy, Portugal and Austria to “send a clear message that those who profit from the consequences of war must do their part to ease the burden on the general public”.

“It would make it possible to finance temporary relief, especially for consumers, and curb rising inflation, without placing additional burdens on public budgets,” the ministers said in a letter on 4 April. The EU’s fossil fuel bill has risen by €22bn since the start of the Iran war.