Following the recent summit of the BRICS (Brazil, Russia, India, China, and South Africa), where the group agreed to add six new members, I argued that neither it nor the G7 (Canada, France, Germany, Italy, Japan, the United Kingdom, and the United States - plus the European Union) has the credibility or the capacity to tackle global challenges. That leaves the G20 (comprising 19 of the world's largest economies, plus the EU) as the only grouping with the legitimacy to offer truly global solutions to global problems.

The joint declaration that emerged from last week's G20 summit in New Delhi provides further confirmation of this. Member states reached a consensus to address a wide range of issues. Despite obvious challenges - such as the considerable differences in how member states operate - they managed to reassert the G20's relevance after a lengthy period in which its role had been called into question.

We should applaud those who played the biggest roles - presumably India and the US - in pushing through the final communiqué. The New Delhi declaration could be the first step in a stronger concerted effort to address global issues like climate change, the need for a revamped World Bank, infectious disease control, economic stability, the war in Ukraine, and other matters. Though this agenda was agreed in the absence of Russian President Vladimir Putin and Chinese President Xi Jinping, the Russian and Chinese representatives who did attend would not have signed on to anything without having cleared it with their respective governments.

Many speculate that Xi skipped the summit in order to snub India - one of China's longstanding rivals - and Indian Prime Minister Narendra Modi. Whatever the motive, his decision had the effect of undermining the significance of the recent BRICS meeting, which many saw as a victory for China.

As I argued last month, the lack of Indo-Chinese solidarity will be a major stumbling block for the new BRICS. Now, Xi's absence from the G20 summit has deepened the divide between the two countries. If Xi wants to convince us otherwise, he will need to reach out to Modi. As matters stand, the success of the G20 meeting makes Modi the clear winner in this season of summitry. Perceptions matter, and right now he looks more like a visionary statesman than Xi does.

Moreover, the G20 achieved another subtle, but important, step by agreeing to expand its ranks to include the African Union - making it a G21. This breakthrough gives Modi a clear diplomatic victory, allowing him to burnish his image as a champion of the Global South. It also further underscores the seemingly random nature of the BRICS' own expansion, which includes Egypt and Ethiopia, but not other, more important African countries, such as Nigeria. The big question now is whether a permanent seat at the table will make the African Union itself a more effective body.

Since the BRICS meeting, I have spoken to people who believe that the G7 is still a highly effective body compared to the G20, as evidenced by the solidarity it has shown on issues like Russia's war in Ukraine. I beg to differ. Though the G20 communiqué's language on the war did not rise to the level that Ukraine's leaders would prefer, it was robust enough to send a clear message to others who may want to violate internationally recognized borders. It also conveys to Putin that he should not expect even superficial backing from some of his supposed BRICS friends. And, of course, the declaration does not inhibit Western countries or individual leaders from condemning the war in more forceful terms.

More to the point, the voice that matters when it comes to Ukraine is not the G7 but NATO - just as the G20 is the collective voice that truly matters when it comes to the global economy, climate change, public health, and many other issues. As much as G7 leaders would like to think that they are still a major influence in global affairs, the reality suggests otherwise. The big takeaway from the New Delhi summit is that you cannot possibly deal with big global challenges unless you include the major emerging powers.

Yes, the G20's critics will counter that it is too large and unwieldy to be effective. But I would simply repeat what I wrote back in 2001, when I first coined the BRIC acronym. If eurozone member states really wanted to demonstrate their belief in the permanence of their joint project, I observed, they would send just one delegate to international gatherings like the G20, rather than retaining their individual representatives. That made the group less unwieldy and set a powerful precedent. If other blocs, including the BRICS, did the same, the result would be a global-governance grouping that is truly fit for purpose.

From Project Syndicate