* Shares of Boeing, Caterpillar fall more than 1 pct

* U.S. stocks to open lower after four days of gains

* TripAdvisor up on Barclays upgrade

* Futures down: Dow 0.75 pct, S&P 0.6 pct, Nasdaq 0.69 pct (Adds comment, details; updates prices)

By Amy Caren Daniel

July 11 (Reuters) - U.S. stocks were set to open lower on Wednesday, halting a four-day run of gains after the United States threatened to impose tariffs on an additional $200 billion worth of Chinese goods, dampening hopes of a compromise on trade.

U.S. officials on Tuesday issued a list of thousands of Chinese imports that the Trump administration wants to target with new tariffs, including hundreds of food products, as well as tobacco, chemicals, coal, steel and aluminum.

China’s commerce ministry said it was “shocked” and would complain to the World Trade Organisation, but did not immediately say how it would retaliate.

“Unfortunately the markets haven’t come to grips with the current levels of trade policies and tariffs,” said Art Hogan, chief market strategist at B. Riley FBR in New York

“Concerns over trade and trade wars are really having an adverse effect, less so on the U.S. markets than the international markets, but it is certainly taking a bite.”

At 8:46 a.m. ET, Dow e-minis were down 187 points, or 0.75 percent. S&P 500 e-minis were down 16.75 points, or 0.6 percent and Nasdaq 100 e-minis were down 50.25 points, or 0.69 percent.

Global stocks were under pressure overnight, with Chinese markets taking the biggest hit. The Shanghai Composite index dropped 1.8 percent and China’s blue-chip CSI300 index 1.7 percent.

There is a two-month period of public comment on the latest proposed list before the tariffs get imposed. President Donald Trump has said he may ultimately target more than $500 billion worth of Chinese goods - roughly the total amount of U.S. imports from China last year.

Among premarket decliners, Boeing, the single largest U.S. exporter to China, and Caterpillar fell around 1.5 percent each, while U.S. Steel dropped 2 percent.

Industrials and metal companies, as well as chipmakers have been the worst hit since Trump first threatened tariffs in early March as they are largely reliant on China for businesses.

Intel, Broadcom, Micron Technology, AMD and Nvidia were down between 0.8 percent and 2 percent.

The escalating trade war sparked a broad sell-off, including in “FAANG” shares, which are generally immune to trade-related news.

Facebook, Amazon, Apple, Netflix and Alphabet were all down between 0.4 percent and 0.9 percent.

U.S.-listed shares of Chinese companies also tumbled, with e-commerce giant Alibaba down 1.5 percent, JD.com off 1.6 percent and Baidu 1.6 percent.

Also weighing on the sentiment was the two-day NATO summit in Brussels where Trump wants Europeans to pay more for their own defense.

Hogan said the meeting had already started on a “sour note”.

TripAdvisor’s shares rose 3.2 percent after Barclays upgraded the stock to “overweight” rating. (Reporting by Amy Caren Daniel in Bengaluru; Editing by Anil D’Silva)