U.S. Treasury Secretary Jack Lew said Wednesday that it is crucial to the United States that China be brought up to world standards for how it regulates and manages its economy. At a business conference hosted by CNBC, Lew said that – despite tensions between the two countries – the United States will remain closely engaged with China to try to further economic reform in the country, which is now the world's second largest economy behind the United States. "Realistically, the global economy depends on a good U.S.-China relationship," Lew said. The Treasury chief also said that in recent talks with Chinese officials he made clear U.S. demands that China stop managing its currency, which is pegged to the value of the American dollar. "I could not be more clear with our Chinese counterparts on the need for them to step back from intervention and for them to move toward a market-determined exchange and to be much more transparent about their actions," Lew said.