BEIJING—A senior Chinese trade official warned that any further appreciation of the Chinese currency risked driving exporters out of business, underscoring the domestic political pressures on Beijing amid growing international calls for China to let the yuan rise.

Vice Commerce Minister Zhong Shan, in an exclusive interview Thursday ahead of a visit to the U.S., said that the profit margin on many Chinese export goods was less than 2%.

Most exporters absorbed the appreciation in the value of the yuan that followed its revaluation in 2005 by boosting innovation and cutting costs, but many were forced to close, he said. A further rise in the currency's value would endanger more exporters' survival, which China can't afford, he said.

U.S. lawmakers and business groups rejected Mr. Zhong's argument, and said China needed to address concerns over its currency if it wanted to avoid further irritaing bilateral tensions.