US levied import tariffs on Chinese-made tires will be investigated by the World Trade Organization in September, the Wall Street Journal reported. Documents published by the WTO on Monday revealed that a Chinese appeal against extra tariffs of 35%, 25% and 20% over of the next three years has prompted the probe. The move by the US led to a series of tit-for-tat trade disputes between China and US, including import tariffs on US nylon, chicken and industrial acid. The WTO’s decision will depend "on how much Chinese tire imports increased, whether U.S. tiremakers were hurt by these imports, and whether the tariffs exceeded what was necessary," said Simon Lester of worldtradelaw.net, a Washington-based consultancy. "It’s more straightforward than most trade remedy cases." The investigation is expected to last for nine months, but any action following a WTO ruling could be delayed for years in the event of US or Chinese appeals.