The U.N. Secretary General has slammed new funding for fossil fuel exploration, describing it as "delusional" and calling for an abandonment of fossil fuel finance.

In remarks delivered via video to the Austrian World Summit in Vienna, Antonio Guterres issued a sobering assessment of the planet's prospects.

"The energy crisis exacerbated by the war in Ukraine has seen a perilous doubling down on fossil fuels by the major economies," he said on Tuesday. "The [well-known events] has reinforced an abject lesson: our energy mix is broken," Guterres said. "Had we invested massively in renewable energy in the past, we should not be so dramatically at the mercy of the instability of fossil fuel markets now."

Concerns related to both the energy transition and energy security have been thrown into sharp relief by Russia's invasion of Ukraine, with the price of both oil and gas continuing to surge in recent months.