"What we're talking about on both sides is a fraction of 1 per cent of both economies", he said, adding that the larger concern is the protection of U.S. intellectual property.
The Dow opened down more than 500 points.
President Donald Trump also downplayed the prospect of a trade war, saying on Twitter Wednesday morning that "we are not in a trade war with China, that war was lost many years ago by the foolish, or incompetent, people who represented the U.S".
But they worry that China's measures targeting USA exports of aircraft, soybeans and other products could help bring on a tit-for-tat trade war of escalating sanctions between the world's two biggest economies.
It's still not clear when the new waves of tariffs announced by the two sides might take effect - or if they'll be watered down in the meantime. "The amount that both countries have invested in bilateral trade cooperation and economic cooperation is so significant that the costs of going back would be very painful, and more than either country would want to bear".
Late on Tuesday, the Trump administration announced 25 percent tariffs on $50 billion of annual imports from China, covering about 1,300 industrial technology, transport and medical products. Both countries are targeting $500 billion in goods.
European stock markets have fallen sharply after China announced a series of tariffs on US goods, stoking fears that the two countries were on the brink of a full-scale trade war. Aerospace company Boeing shed $14.07, or 4.3 percent, to $316.75. Farming states were also among Trump's staunchest supports in the election.
Wang said the trade gap is not as big as the USA claims.
The big worry on Wall Street is that corporate profits and sales will be hurt if trade restrictions are put in place, which would be a major negative for stock prices. The Nasdaq composite declined 30 points, or 0.4 percent, to 6,910.
"We understand some big-picture concern but it appears to us that the specific proposals from China this morning are calibrated carefully to avoid a major impact on Boeing and are therefore intended more as a message to the USA administration that additional trade barriers will be met with an escalating response", said JPMorgan analyst Seth Seifman.
Trade tensions between China and the U.S. have been ramped up after Beijing responded to United States plans for putting new taxes on hundreds of Chinese imports.
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They, however, promised not to screen the film in its entirety till the Los Angeles premiere, before the film's worldwide release. A new commercial for Rocket Mortgage features the Avengers in an attempt to promote Avengers : Infinity War .
Ontario Apple Growers general manager Kelly Ciceran says the 15 per cent tariff on fruit such as apples, cherries, peaches, raspberries and cranberries will likely lead to more US produce hitting Canadian stores.
"If the US decides to increase intensity, China will surely follow suit", said Tu. Kent Bacus, director of worldwide trade and market access for the National Cattlemen's Beef Assn., said although unsettling, the group wasn't surprised to see beef as a target for retaliation, as it is an inevitable outcome of any trade war.
"It is nobody's best interest for the United States and China to engage in a trade war", said Sam Stovall, chief investment strategist at CFRA Research.
However, there was no evidence yet of an organized campaign to stoke anti-U.S. behavior, or that consumers were yet shunning USA goods in any numbers.
A man walks by an electronic board displaying stock trading index at a brokerage house in Beijing, Tuesday, April 3, 2018.
The goal was to address China's overproduction, but the measures also would hit allies, prompting the European Union to threaten retaliation.
American and other foreign companies have long complained about Chinese rules that require automakers and others to work through local partners, compelling them to share technology with potential competitors.
"In the event of all-out trade war, both may lose all sense of reason, but I do hope it will never happen".
Most investors agree that tariffs are bad for business and the economy. He said that will stir up political pressure against the trade sanctions.
If there is a silver lining it is that much of the jawboning is viewed as part of the negotiation process, he adds. But Wednesday's retaliation round will be far more costly to United States exporters. There will likely be negotiation.