Putin told the gathering of presidents of ex-Soviet countries and business leaders that 60 per cent of the world's GDP was produced outside the Group of Seven (G7) leading nations - the US, France, Germany, Britain, Japan, Italy and Canada.
He proposed the creation of "regional Eurasian free trade organisations" that would draw on the experience of the WTO.
Together with Sergei Ivanov, a senior minister widely tipped to become Russia's next president, Putin had spent Saturday assuring the world's business elite that in spite of rising tensions between Moscow and the West, Russia was a safe bet.
The criticism of the WTO reflected Moscow's frustration in its struggle for recognition, not only as a rapidly growing economy, but as a major world power.
Russia has clashed repeatedly with the US and Europe in recent months, both over political issues such as the status of Kosovo and US missile defence plans, and on economic issues related to Russia's WTO accession.
While Putin spoke, German Gref, the Russian economic development and trade minister, held talks with EU, US, and WTO negotiators on Russia's final push to join the world body.
On Saturday, around 3,500 people marched through St Petersburg's historic city centre shouting "Shame on the Kremlin, shame on the authorities" and "Russia without Putin".
Some carried posters saying "Putin - Wanted" while others complained about the Kremlin's tight control of the airwaves, which keeps most opposition figures off television and radio shows.
In sharp contrast to other opposition demonstrations in past months, which were broken up by baton-wielding riot police, the march was allowed by the authorities.
"The authorities didn't want to ban the protest during the forum," Garry Kasparov, world chess champion turned opposition leader, said.
Andrei Illarionov, who served as an economic adviser to Putin before resigning to join the opposition last year, advised those at the forum to think again about participating.
"Businessmen," he said in a speech to the crowd. "If you want to help Russia to become stronger and better, come to our march instead of going to the Forum."