WASHINGTON, Nov 15 (Reuters) – China Telecom's (0728.HK) U.S. subsidiary on Monday asked a U.S. appeals court to block the decision of the Federal Communications Commission to revoke the telecommunication company's authorization to operate in the United States. China Telecom Americas was ordered by the FCC to discontinue U.S. services by early January after the U.S. regulator cited national security concerns. The Chinese telecom company told the U.S. Appeals Court for the District of Columbia on Monday it must notify customers of the decision by Dec. 4. China Telecom, the largest Chinese telecommunications company, has had authorization to provide telecommunications…