The trade war with China is on

The trade war with China is on. At 00:01 am EST on July 6, Donald Trump’s list of tariffs on Chinese imports is taking effect.

China immediately said it would be forced to retaliate.

The duties on Chinese goods started at 12:01 a.m. Friday in Washington, which is just after midday in China. Another $16 billion of goods could follow in two weeks, Trump earlier told reporters, before suggesting the final total could eventually reach $550 billion, a figure that exceeds all of U.S. goods imports from China in 2017.

U.S. customs officials will begin collecting an additional 25 percent tariff on imports from China of goods ranging from farming plows to semiconductors and airplane parts. China’s officials have previously said they would respond by imposing higher levies on goods ranging from American soybeans to pork, which may in turn prompt Trump to raise trade barriers even higher.

It’s the first time the U.S. has imposed tariffs directly aimed at Chinese goods following months in which Trump accused Beijing of stealing American intellectual property and unfairly swelling America’s trade deficit.

The riskiest economic gamble of Trump’s presidency could spread as it enters a new and dangerous phase by imposing direct costs on companies and consumers globally.

“Once these tariffs start going into effect, it’s pretty clear the conflict is real,” said Robert Holleyman, former deputy U.S. trade representative under President Barack Obama and now a partner at law firm Crowell and Moring LLP. “If we don’t find an exit ramp, this will accelerate like a snowball going down a hill.”

Recent U.S. tariffs on steel and aluminum antagonized fellow developed nations and drew return fire from countries including the European Union and Canada.