China announced yesterday it will impose additional tariffs of up to 15% on imports of major U.S. farm products, including chicken, pork, soy and beef, and restrict exports to 15 U.S. companies. The tariffs, announced by the Commerce Ministry, are due to take effect from March 10, though goods already in transit will be exempt until April 12. The measures come after U.S. announced it would raise tariffs on imports of Chinese products to 20% across the board, which took effect yesterday