The Dow Jones industrial average rose on Thursday, but the S&P 500 and Nasdaq composite closed lower as investors assessed the possibility of a trade war.
The 30-stock index rose 115.54 points to close at 24,873.66, with UnitedHealth contributing the most to the gains. Earlier in the session, the Dow rose nearly 300 points. Boeing, which has struggled throughout the week, fell 0.1 percent in choppy trade Thursday.
"Boeing got hit three days in a row earlier in the week because people felt that was a way the Chinese and others could" retaliate, said Art Cashin, director of floor operations for UBS, on CNBC's "Squawk Alley."
"You're going to get that kind of ebb and flow," Cashin said. "I would continue to keep my eye on Boeing. I think it's going to be the critical factor in the Dow."
The fell 0.1 percent to 2,747.33, with losses in materials offsetting a 0.3 percent gain in industrials. The Nasdaq composite pulled back 0.2 percent to 7,481.74.
The White House is thinking about implementing tariffs on at least $30 billion of Chinese imports as part of a package of anti-China measures, the Wall Street Journal reported. Reuters also reported Tuesday that President Donald Trump may impose tariffs on $60 billion of Chinese goods.
Investors worry that other countries could retaliate by implementing their own tariffs on U.S.-made goods and sparking a trade war. This would hurt companies who do business overseas, especially large multinationals like Boeing.
"There are two specific reasons these fears are hitting stocks," said Tom Essaye, founder of The Sevens Report. "First, the Trump administration is specifically targeting intellectual property theft by the Chinese government, a practice that most independent analysts admit is rampant. … By targeting IP, the administration can cast a very wide net as far as what products it can slap tariffs on."
"Second, the law by which the Trump administration is conducting the investigation, Section 301 of the Trade Act of 1974, gives the president widespread and virtually unchallenged authority to take retaliatory trade actions," Essaye said.
Stocks were also pressured Thursday after The New York Times reported that special counsel Robert Mueller subpoenaed Trump's businesses and the Trump Organization "in recent weeks."
The moves Thursday come after Wall Street saw a choppy trading day on Wednesday, with the Dow Jones industrial average closing almost 250 points down. Shares of Boeing contributed the most to the losses, as concerns that a trade war could occur between the U.S. and China came to the surface.
Stocks tried to rebound after news broke that Larry Kudlow would become the next National Economic Council directors, replacing Gary Cohn, but failed to erase their losses.
Last week, Trump signed two declarations which would implement tariffs on steel and aluminum imports — both of which are expected to take effect in the coming weeks.
However, Peter Navarro, director of the White House National Trade Council, said in an interview Thursday the U.S. can institute tariffs without sparking a global trade war.
"Our allies have got to understand that we're simply defending ourselves against what's been an unfair relationship for many, many years," Navarro said on "Squawk on the Street." "This is going to work out fine. The world's going to be a better place."
In corporate news, Williams-Sonoma reported better-than-expected earnings and revenue for the previous quarter. The company's stock rose 2.5 percent on the back of the news.
Walmart, meanwhile, slipped 0.2 percent amid reports that a former executive is suing the company, alleging unlawful conduct in its e-commerce business.