BEIJING, March 2 (Reuters) – Global trade will be harmed if countries follow the example of the United States, China’s foreign ministry said on Friday, after President Donald Trump said he would impose tariffs on imported steel and aluminum to protect U.S. producers. Ministry spokeswoman Hua Chunying made the comment at a regular news briefing, adding that President Xi Jinping’s top economic adviser Liu He had constructive exchanges on economic issues with U.S. officials in Washington on Thursday.