President Trump is enacting a 25 percent tariff on $50 billion of Chinese goods "that contain industrially significant technologies," after months of exchanging threats amid concerns over a potential trade war.

U.S. Customs and Border Protection will begin to collect tariffs on the first $34 billion worth of Chinese imports on July 6, with more of the taxes planned.

The White House had set a June 15 deadline for announcing the full list of items that will see a tariff imposed, focusing on areas of China's industry such as aerospace, robotics and machinery. Released today, the list includes some 1,100 products.

Trump announced on Friday:

"My great friendship with President Xi of China and our country's relationship with China are both very important to me. Trade between our nations, however, has been very unfair, for a very long time. This situation is no longer sustainable. China has, for example, long been engaging in several unfair practices related to the acquisition of American intellectual property and technology."

China has threatened to retaliate forcefully for any tariffs, listing U.S. products that range from sorghum, soybeans, meat and whiskey to airplanes and cars.

China buys some $14 billion in U.S.-produced soybeans every year — nearly a third of the American crop.

On Friday, Chinese foreign ministry spokesman Geng Shuang said China will act quickly to "take necessary measures to defend our legitimate rights and interests."

It's the latest round of tariffs imposed by the Trump administration, which hit U.S. allies Mexico, Canada and the European Union with a round of taxes on steel and aluminum imports in May. Trump cited the interests of national security as the motivation behind that move.

The American tariffs will come in two phases, the U.S. Trade Representative's office said on Friday, with the tariff on some $34 billion worth of Chinese imports set to take effect on July 6.

"The list does not include goods commonly purchased by American consumers such as cellular telephones or televisions," the U.S.T.R. office said.

A second list, which ranges from chemicals and plastics to motorcycles and technical equipment worth some $16 billion, is made up of proposed items — and will not be finalized until after a public hearing.

Trump first mentioned the tariffs in March; since then, the White House has sent mixed messages on the plan – and it has also sent envoys to China and received Chinese representatives as the two countries' trade and finance officials negotiated.

As he made the U.S. tariffs official, Trump said that "if China engages in retaliatory measures, such as imposing new tariffs on United States goods, services, or agricultural products," his administration would impose new tariffs in response.

Progress seemed to be made in late May, after China agreed to cut tariffs on U.S. automobiles, and Trump pledged support for ZTE, a Chinese company affected negatively by U.S. sanctions, as NPR's Camila Domonoske reported.

America's trade in goods with China topped $635 billion in 2017, according to the U.S. Census Bureau. In that year, the U.S. says its goods trade deficit with China was $375.2 billion.

The White House announced the tariffs one day after Secretary of State Mike Pompeo visited Chinese President Xi Jinping in Beijing for talks that were described as focusing on Trump's recent meeting with North Korean leader Kim Jong Un.

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