The United States should consider the spillover effect of its monetary policy, especially the timing and pace of its exit from the ultra-loose monetary policy known as quantitative easing, said a Chinese official ahead of the Group of 20 nations summit scheduled for Sept 5 to 6 in St. Petersburg, Russia.

Minimizing the negative impact on other nations as the US Federal Reserve "tapers off" QE will be high on the agenda at the summit, which will bring together the leaders of developed and developing nations.

"The United States ... must consider the spillover effect of its monetary policy, especially the timing and rhythm of its withdrawal from the ultra-loose monetary policy," Vice-Minister of Finance Zhu Guangyao said at a news conference on Tuesday in Beijing.

However, Yi Gang, a deputy governor of the central bank, told the same briefing that an exit from QE may have only a "limited" effect on China, compared with other emerging economies.

"The impact on China is not that obvious," Yi said.

Experts said the officials' comments underscored China's increasing concern about the uncertainty posed by a possible tightening of previously abundant liquidity.

Such concerns have already hit some emerging economies such as India, Indonesia and Brazil.

The minutes from the latest Fed meeting in July strengthened market expectations that it will reduce its bond-buying program in September.

Ding Zhijie, dean of the School of Banking and Finance at the University of International Business and Economics, said China has stronger financial "firewalls" than other countries such as India, including capital-account controls.

However, Ding said, the actual damage to China caused by US policies could be larger than for other emerging economies.