U.S. stocks traded lower Monday morning after data on the U.S. manufacturing sector showed it continuing to contract in November, overshadowing better-than-expected data on Chinese manufacturing released late Sunday.

Investors were also monitoring trade concerns after President Donald Trump announced via Twitter that the U.S. would restore tariffs on all steel and aluminum shipped into the U.S. from Brazil and Argentina.

What are major indexes doing?

The Dow Jones Industrial Average DJIA, -0.82% fell 134 points, or 0.5%, to 27,918, while the S&P 500 index SPX, -0.88% lost 20 points, or 0.6%, to 3,121. The Nasdaq Composite Index COMP, -1.35% fell 91 points or 1%, at 8,574.

Stocks ended lower in an abbreviated session Friday following the Thanksgiving Day holiday, but posted solid November gains. The Dow fell 112.59 points on Friday, or 0.4%, to end at 28,051.41, leaving it with a 3.7% monthly gain. The S&P 500 declined 12.65 points, or 0.4%, to close at 3,140.98, booking a 3.4% monthly rise. The Nasdaq Composite lost 39.70 points, or 0.5%, to end at 8,665.47, notching a 4.5% monthly gain.

Read: Will a Santa Claus rally power the S&P 500 and Dow to their best years in a generation?

What’s driving the market?

U.S. stocks were weighed by data on the U.S. manufacturing sector that showed it contracting for the fourth straight month, with the Institute for Supply Management’s purchasing manager’s index unexpectedly falling to 48.1% in November from 48.3% in October. Economists polled by MarketWatch expected a reading of 49.2%. Readings below 50% reflect business conditions worsening.

The data overshadowed a separate survey on U.S. manufacturing by Markit, which showed the sector gaining steam, with a 52.6 reading, versus October’s 52.2.

Investors also got a reminder of the potential for negative trade headlines, with futures paring gains in earlier activity after Trump accused Brazil and Argentina of “presiding over a massive devaluation of their currencies, which is not good for our farmers.” Trump tweeted that, effective immediately, “I will restore Tariffs on all Steel & Aluminum that is shipped into the U.S. from those countries.”

See: Trump brings back tariffs on Brazil and Argentina as deadline for China levies approaches

Meanwhile, China is insisting that U.S. tariffs be rolled back as part of any “phase one” trade deal, China’s state-run Global Times said Sunday. And Axios reported Sunday that deal is unlikely to be agreed upon before late December, but that Trump is expected to put off tariff hikes scheduled to take effect Dec. 15 to keep negotiations alive.

Stock-index futures had been trading higher in premarket action early Monday after data showing a pickup in manufacturing activity in China. The Caixin manufacturing purchasing managers index rose to 51.8 in November from 51.7 in October, Caixin Media Co. and research firm Markit said Monday — with the reading remained above the 50 level that separates expansion from contraction. Earlier, China’s official manufacturing PMI reading moved back into expansion activity, rising to 50.2 in November from 49.3, according to the country’s National Bureau of Statistics, marking the first reading above 50 for the index since April.

Investors will also be keeping an eye on retail stocks as the so-called Cyber Monday shopping day gets under way. Adobe Analytics said this year’s Black Friday was the biggest ever for online sales, coming in at $7.4 billion and ranking just behind last year’s Cyber Monday haul of $7.9 billion. Adobe forecasts online sales to hit $9.4 billion this Cyber Monday.

In other economic data, the government said that construction spending fell 0.8% in October from a 0.3% decline in September. Economists were expecting a 0.4% increase, according to a MarketWatch poll.

Which stocks are in focus?

Dow Component Intel Corp.’s INTC, -0.44%  stock fell 0.1% Monday after it announced the completion of the sale of the majority of its smartphone modem business to Apple, a $1 billion deal announced July 25.

Shares of Wells Fargo & Co. WFC, -1.20%  edged down 0.7% early Monday, after Raymond James analyst David Long cut his rating on the bank’s stock from to underperform from market perform.

McDermott International Inc. MDR, +6.96%  stock rallied 9.3%, after the energy-services company announced access to $350 million in financing and a forbearance agreement with some of its creditors.

Amazon.com Inc. AMZN, -1.81%  stock was down 1.3% as Cyber Monday got under way, one of the most important days of the year for the online retail giant.

See: Amazon pulls Auschwitz ‘Christmas ornaments’ after protest

Shares of Apache Corp. APA, -11.96%  were down 12.2% after the firm gave an update on the status of a new offshore well, Maka Central #1, off the coast of Suriname, but provided no new information on site’s potential profitability.

How are other markets trading?

The yield on the 10-year U.S. Treasury note TMUBMUSD10Y, +2.86%  rose 5.2 basis points to 1.832% on positive manufacturing data.

In commodities markets, the price of West Texas Intermediate crude oil for January delivery CLF20, +1.45%  rose $1, or 1.8%, to $56.17 a barrel on rising hopes for global growth. The price of an ounce of gold for December delivery GCZ19, -0.17%  fell $4.90, or 0.3%, to 1,460.70 as demand for havens waned.

The U.S. dollar edged 0.3% lower, according to the ICE U.S. Dollar index DXY, -0.34%.

In Asia overnight, stocks closed mostly higher, with the China CSI 300 000300, +0.10%  rising 0.1%, Japan’s Nikkei 225 NIK, +1.01%  adding 1% and Hong Kong’s Hang Seng Index HSI, +0.37%  gaining 0.4%. European stocks were trading mostly lower, reflected by the 1.2% decline for the Stoxx Europe 600 SXXP, -1.42%.