Since the early days of his G20 leadership, Brazil’s President Lula put fighting inequality centre stage, and at the Heads of State Summit this week, delivered a groundbreaking agreement that could begin to tackle the extreme and destructive chasm between the super-rich and the rest. Leaders meeting in Rio signed and sealed a historic deal to work together to tax the world’s wealthiest people — a deal that the world sorely needs and that the richest can easily afford.

We live in a world that delivers extreme wealth for the few while leaving hundreds of millions of people hungry — another top item on the agenda of leaders in Rio, where they launched the Global Alliance Against Poverty and Hunger. The richest people amass billions of dollars, and a small wealthy elite has more money than they could spend in several lifetimes. Today, the world’s 16 richest individuals would still be billionaires even if 99 percent of their wealth vanished overnight.

Despite this wealth explosion at the top, taxation on the world’s wealthiest has plummeted in recent decades. The richest 1 percent in the G20 have seen their tax rates fall by roughly a third since 1980, a period where their income share increased by 45 percent. The reality is that most of us are contributing a far higher share of our income and wealth through taxation than even billionaires do. For example, Elon Musk — one of the richest men in history — has been shown to pay a ‘true tax rate’ of just 3.2 percent. The likelihood is that you pay significantly more than this. For the world’s poorest people, the injustice is even greater: Aber Christine, a market trader working with Oxfam Uganda, pays 40 percent of her profits in tax. Given this obscene inequality, it is small wonder people around the world are rising up and demanding action to tax the super-rich.

Increasing taxes on the global economic elite has the potential to raise the trillions of dollars that governments everywhere need for public spending on everything from teachers to green technology, providing the investment necessary to end extreme poverty and address the imminent climate catastrophe.

This G20 agreement comes as the debate rages at COP29 in Baku about how much governments, particularly from the highest-emitting countries, are willing to spend on tackling the climate crisis and making amends to the poorest people and countries who bear the brunt of the impact. Activists and civil society groups are demanding rich nations pay at least $5 trillion in climate finance to the Global South, yet as COP nears completion, the draft text indicates that as little as $350 billion could be on the table — a woefully inadequate amount, and one that seems indefensible just days after the 20 richest countries on the planet committed to action to tax the ultra-wealthy that could raise trillions.

The very existence of a super-rich elite which splurges on polluting superyachts and private jets is turbocharging global warming and putting the future of humanity at risk. Oxfam analysis released this year revealed that if everyone emitted carbon at the same rate as just the luxury transport emissions of 50 of the richest billionaires, our remaining carbon budget would be gone in just two days. The lifestyle of people with billions of dollars to spare is quite simply incompatible with a sustainable future for people and planet.

Under President Lula’s G20 leadership the world has seen growing political momentum on taxation of the richest individuals. Back in July, Finance Ministers committed to ‘engage cooperatively to ensure that ultra-high-net-worth individuals are effectively taxed’ on the basis that ‘wealth and income inequalities are undermining growth and social cohesion.’ Despite this pre-existing shared commitment, there was some jeopardy in Rio. It was reported that negotiators from Argentina ‘vehemently opposed’ language on taxing ultra-high-net-worth individuals in the Rio G20 Declaration.

It’s a testament to the resolve of other G20 countries that the commitment remained in the face of this opposition. It offers hope that there is the requisite political will to make it a reality. So, too, does the subsequent IBSA communique where India, Brazil and South Africa applaud success on the issue and call for an early protocol on the effective taxation of high-net-worth individuals under the UN Tax Convention. Separately, South African President Ramaphosa underlined that ‘taxation of the ultra and super-rich’ was an ‘important aspect of what Brazil has just achieved’, giving rise to further hope that he will progress this agenda under his G20 Presidency, which officially commences on 1 December.

As ever, though, the proof of the pudding will be in the eating. And that proof won’t come until this G20 agreement becomes a global deal to tax the super-rich at rates high enough to reduce inequality, alongside measures to curb illicit financial flows that allow the super-rich to evade their tax responsibility. The world can’t afford to wait much longer.