The handshake between then UK prime minister Tony Blair and Muammer Gaddafi in the desert in 2007 was not just the moment the Libyan leader cemented ties with an old foe. It was also a stark symbol of the role “Big Oil” played in foreign policy.

BP sealed a significant exploration deal on the same trip, which capped its efforts to nudge the UK government to re-establish ties with the late North African dictator while opening access to huge hydrocarbon resources on Europe’s doorstep.

The struggle for fossil fuel resources has influenced geopolitics for decades, from generating conflict and shaping relations between the west and Middle East to today’s controversy over the Nordstream 2 pipeline from Russia to western Europe.

But now the relationship between western oil companies and their governments is undergoing a dramatic shift as governments commit to going green and fossil fuels fall out of favour — a move that gathered pace in April when US president Joe Biden convened an international climate summit to put pressure on countries to cut emissions.

“There has always been the notion that geopolitical power writ large was tied to oil access,” said Greg Priddy, a former energy analyst for the US government. “Even as late as the Obama administration in the US there was a sense that major producers overseas were strategically important. But all that is changing. ”