American President Donald Trump says his administration will propose banning thousands of flavors of electronic cigarettes, known as e-cigarettes. The Food and Drug Administration (FDA) will develop rules to remove all e-cigarette flavors, except tobacco, from the U.S. market. Health and Human Services Secretary Alex Azar made the announcement Wednesday. He spoke at the White House during an appearance with the president, first lady Melania Trump and the acting chief of the Food and Drug Administration (FDA), Ned Sharpless. E-cigarettes are a popular substitute for traditional smoking products. They have been available in the United States for more than 10 years. The electronic devices heat liquid into vapor -- very small particles that users inhale. Many users vape with a liquid that includes flavoring, nicotine and other chemicals.