China has become an engine of global growth and US exports, and deepening bilateral economic ties is of critical importance to both nations, US Treasury Secretary Timothy Geithner said Thursday.

"We live in a global economy, and this global economy will be a potential source of economic growth for the United States, but also a source of challenges," he said in a speech at the Commonwealth Club of California in San Francisco.

The US President Barack Obama recognized that to confront the global financial crisis, "we had to work to support growth around the world, not just focus on putting out the financial fires in the United States," Geithner said prior to the upcoming fourth round of the China-US Strategic and Economic Dialogue (S&ED).

Parts of the world, and particularly emerging markets, have been a source of strength for the United States since the financial crisis. China has been a significant part of this growth, according to his prepared speech.

"The economic relationship between the United States and China provides significant benefits to both our nations. Even though we compete in many areas, our economic strengths are largely complementary," he said.

"Our priorities in our economic relationship with China -- from its exchange rate to its treatment of intellectual property -- reflect changes that are fundamentally in China's interest and essential for sustainable economic growth," Geithner stressed.

The top economic aide in the Obama administration said that one of the US strategic objectives was to expand bilateral cooperation on a range of international economic and financial fronts to better tackle common global challenges including the ongoing European crisis.

Since early 2009, US exports of goods to China have almost doubled, growing twice as fast as US exports to the rest of the world. In 2011 alone, the United States exported around 130 billion US dollars in goods and services to China, supporting more than 600,000 jobs in the United States, according to Geithner.

The fourth round of the China-US S&ED, a high-level consultation platform between the world's two largest economies, is to be held in Beijing from May 3-4, according to the Chinese Foreign Ministry.