(NAFB.com) – The U.S. and China have begun charging competing port fees on ocean shipping firms that move everything from holiday toys to crude oil. Reuters said the new fees will make the high seas a key front in the continuing trade war between the world’s biggest economies. China has started collecting the levies on U.S.-owned, operated, built, or flagged vessels, but clarified that Chinese-built ships are exempt from the same levies. The China-imposed extra port fees will be collected at the first port of entry on a single voyage or the first five voyages within a year. Earlier this year, President Donald Trump announced plans to levy fees on China-linked ships to loosen the country’s grip on the global maritime industry and boost U.S. shipbuilding. Yahoo said an investigation during former President Joe Biden’s administration found that China uses unfair trade policies and practices to dominate the global maritime, logistics, and building sectors.