A historic drop in greenhouse gas emissions and energy consumption during the height of the Covid-19 pandemic rapidly reversed course last year when the dirtiest fossil fuel made a comeback, according to oil giant BP Plc.

The findings show the difficulty of achieving pledges from last year’s COP26 climate talks, where delegates clinched a historic deal to curb coal use in an attempt to limit global warming to 1.5 degrees Celsius from pre-industrial times, the level that scientists say is needed to avoid catastrophic warming.

“Carbon emissions have risen in every year since the Paris goals were agreed” apart from 2020, BP Chief Economist Spencer Dale said. “The world remains on an unsustainable path.”

Primary energy demand rebounded by 5.8% last year, surpassing 2019 levels, according to BP’s annual Statistical Review of World Energy, published Tuesday. Fossil fuel consumption was steady from pre-pandemic levels, accounting for 82% of total energy usage, with coal consumption surging more than 6%. That’s despite significant price increases in Europe and Asia.

Meanwhile, global oil demand grew by 5.7 million barrels a day, according to BP, but was still 3.7 million barrels a day below pre-pandemic levels, as the aviation industry in particular struggled to recover passenger numbers.

Global natural gas consumption also gained about 5% year-on-year, with prices surging fourfold to record levels in Europe and tripling in the Asia spot market.

With Covid-19 restrictions largely lifted around the world and economic activity rebounding, “energy consumption is expanding sharply, increasing the demands on available energy supplies and highlighting fragilities in the system,” Dale said in the report.

The war in Ukraine has sent countries rushing to secure alternative oil and gas supplies in a bid to replace Russian energy. The Group of Seven nations, which is wrapping up a meeting in Germany Tuesday, is evaluating how prices of Moscow’s crude can be curbed to limit revenues flowing to President Vladimir Putin’s government. The group is also set to allow public financing of overseas fossil-fuel projects to continue in limited circumstances as a result of the crisis.

Last year’s global increase in energy use resulted in a rebound of greenhouse gas emissions, which had seen a sharp drop in 2020. That said, there were encouraging signs of growth in renewables, Dale said, with strong expansion in wind and solar, accounting for 13% of total power generation.

“The low-carbon energy sources and technologies needed to achieve a fast and deep decarbonization exist today,” Dale said. “The challenge is to apply them at unprecedented pace and scale.”