Vladimir Putin
Russia's President Vladimir Putin speaks during a session of the St. Petersburg International Economic ForumReuters

Russia's President Vladimir Putin has said the United States' unipolar vision of the world has failed and warned that sanctions imposed on Russia over the Urkaine crisis would have a boomerang effect on the West.

Speaking at Russia's annual global business forum in St Petersburg, Putin pledged to revive the country's ailing economy and shift away its reliance on energy exports.

"The world has changed," Putin told the annual St Petersburg International Economic Forum. "The unipolar vision of the world ... has failed."

He also attempted to split the European Union (EU) from the United States, praising European businesses for taking a "pragmatic" approach over sanctions than American companies.

The European Union has been more reluctant to impose tough sanctions on Moscow as it relies on Russia for a third of its gas needs and has extensive trade ties as well.

Top executives from US firms did not attend the event, instead sending lower level execs, after pressure from the White House to withdraw.

A senior government official said that the Western sanctions were starting to have a serious impact. Washington and Brussels imposed travel bans and asset freezes on dozens of individuals with ties to the Kremlin. A handful of companies were also sanctioned.

Russia's economy is "already in recession" according to the IMF, after massive capital flight in the first quarter.

Russia suffered rapid capital flight in the first quarter of 2014, when investors withdrew $50.6bn (£30bn, €36.6bn) over the intervention in Ukraine and annexation of Crimea.

Some analysts estimated that capital outflow reached more than the $63bn total that left Russia in 2013.