At the personal level, too, as the June G8 summit in Northern Ireland demonstrated, Putin can hardly name a political friend among the other seven G8 members. BRICS, on the other hand, is too diverse a group with vastly different values and interests to function as more than a figurehead for the non-West. Besides, the emerging economies have lost some of their glitz in recent times.

Therefore, Russia feels more at ease in the G20, which brings together both Western and non-Western countries. But being essentially an energy, raw materials and arms exporter, its real interests in global economic management are relatively limited. Russian commentators sometimes muse about the country's bridging role in the world, but in reality successful international mediation has so far proven difficult for Moscow.

The G20 leaders need to tackle serious challenges. The economic recovery in the US remains fragile, with the quantitative easing policy on its way out. The euro has survived, but the debt crisis in the European Union is not over. China's stellar economic growth has been slowing down. India and South Africa have seen their currencies losing massively against the dollar. And the jury is still out on Japan's economic policies, or "Abenomics".

True to form, Russia has laid down a set of priorities for its G20 presidency, which sound generally right - except that the issues on the list are very distant from Russia's own economic preoccupations. Russia more or less manages to present a seemingly relevant economic agenda without serious engagement on its own part, as was seen at last year's Asia-Pacific Economic Cooperation summit in Vladivostok.

It was a year ago that Russia finally joined the World Trade Organization. So far, the result of its membership has been mixed. In a year, Russia's exports have contracted by 0.7 percent and its imports have increased by 1.4 percent. It has trade disputes with the EU and a mini-trade war with Ukraine. Moscow also has warned Kiev against associating with the EU and has been pushing it to join the Customs Union with Belarus, Kazakhstan and Russia.

Within the Customs Union itself, Moscow recently had to resort to trade restrictions to try to get the release of its leading potash company CEO lured by and being held a de facto hostage in Belarus over a business dispute.

Indeed, economics and politics are closely intertwined in the post-Soviet world.

The author is director of the Carnegie Moscow Center.