BERLIN (AP) — The author of an influential report 50 years ago challenging the idea of unlimited economic growth said Tuesday that rising inequality coupled with climate change could lead to social collapse in some countries unless wholesale changes are made — paid for by the world's richest nations.

Jørgen Randers, a Norwegian academic who co-wrote the 1972 book “Limits to Growth” published by the Club of Rome think tank, said governments are increasingly struggling to get popular support for necessary measures to tackle global warming because many current policies disproportionately burden lower income groups that are already struggling financially.

“If the decline in well-being is allowed to last long enough I expect societal breakdown in vulnerable nations and a dangerous decline in the ability of governments to handle the situation,” he told reporters in Berlin at the launch of a new study by the group, titled “Earth4All.”

With studies showing that the wealthiest 10% of humanity are responsible for about half the world's emissions, the new report argues that it is the rich who need to step up to fix the problem.

“Unless the rich pay the bill we will not get the broad voter support for the strong collective action that is needed to increase the well-being of the global majority,” said Randers.

Johan Rockström, who heads the Potsdam Institute for Climate Impact Research and co-authored the latest report, said billions of people are already at risk from climate change worldwide, citing the current deadly floods in Pakistan. This could rapidly worsen if planetary tipping points are crossed — such as if Atlantic Ocean currents slow, he said.

Countries such as Germany, which has a high degree of economic inequality, should therefore lead the way in showing that it's possible to shift to a low-carbon economy without hurting those who are already financially vulnerable, he said.

The report's authors said declining prosperity is seen not just in developing countries, but across Europe and the United States as well, warning that this could spill over into frustration which might cripple governments.

Their suggestions include raising taxes on the wealthiest 10% of individuals and companies for a fund to ease extreme poverty, empower women, improve the global food system and phase out fossil fuels use.