The U.S. Dept. of Commerce considers India to be one of America's most promising export markets. However, the promise will take longer to be fulfilled than previously anticipated, a result of economic sanctions the Clinton Administration imposed in the wake of India's May 11 nuclear tests. Immediately affected were $500 million worth of U.S. exports for which Indian buyers were seeking U.S. Export-Import Bank financing. An additional $3.5 billion worth of exports could be affected. Also put on hold are Overseas Private Investment Corp. risk-insurance and finance packages for India not approved prior to May 13.