China, the largest holder of U.S. debt, can rest assured its investments are safe, the new U.S. Ambassador Gary Locke said in Beijing. Locke said despite the recent U.S. credit-rating downgrade by Standard & Poor\'s, buyers continue to acquire U.S. Treasury bonds, China Daily reported. \"It\'s a clear indication that investment in the U.S. is safe, secure and that the economy, while having its challenges, is still strong,\" he said Sunday. More than half of China\'s foreign-exchange reserves of $3.2 trillion are in U.S. bonds, but the downgrade has raised concerns in China about their safety. Beijing has urged Washington to take \"responsible\" measures to raise market confidence in the U.S. dollar and the U.S. debt, China Daily reported. Locke, who arrived in Beijing during the weekend, said U.S. President Barack Obama has mapped out a \"path ensuring the fiscal integrity\" of the United States.. Locke, former U.S. commerce secretary, is the first Chinese-American to represent the United States in China. He said his new job is to \"build new friendship between the people of the U.S. and China, and to continue to expand our two countries\' growing cooperation and collaboration on key bilateral and international issues.\" When asked whether the United States will continue to sell arms to Taiwan, a sore issue with Beijing, Locke was quoted as saying U.S. policy toward Taiwan is very clear and that will not change.