The United States has agreed in principle to a trade pact with the People's Republic of China involving imports of Chinese textiles and clothing, special trade representative Reubin Askew said Thursday. Details of the agreement will not be released until the pact is initiated by representatives of both countries , probably next week. China is the only major exporter of textiles with which the US does not have a bilateral trade agreement. A decade ago, China exported virtually no textiles and clothing to the US. It is now the fifth-largest supplier, behind Hong Kong, Korea, Taiwan, and Japan.