By Johann M Cherian and Pranav Kashyap

(Reuters) - Wall Street's main indexes fell on Monday as U.S. President Donald Trump's comments over the weekend stoked fears that a trade war could spark an economic slowdown, with the tech-heavy Nasdaq and the benchmark S&P 500 near five-month lows.

At 09:50 a.m. ET the Dow Jones Industrial Average fell 307.75 points, or 0.72%, to 42,492.47, the S&P 500 lost 74.89 points, or 1.30%, to 5,695.31, and the Nasdaq Composite lost 371.78 points, or 2.03%, to 17,826.75.

Mega-cap growth stocks felt the heat. Nvidia fell 2.2%, while Meta and Amazon.com were down more than 3% each.

Tesla was down 7%, lowest since November 5, after UBS cut its forecast for the automaker's first-quarter deliveries and lowered its price target on the stock.

The technology sector lost 2.6%, leading sectoral declines on the S&P 500. The domestically focused small-cap Russell 2000 index fell 1%.

JPMorgan Chase and Goldman Sachs declined more than 3% each, weighing on the broader banks index.

In an interview on Sunday, Trump declined to predict whether the U.S. could face a recession, at a time when investors are concerned that his fluctuating trade policies on Mexico, Canada and China could dampen consumer demand and corporate investment.

China's retaliatory tariffs on select U.S. imports are set to take effect on Monday, with U.S. tariffs on certain base metals anticipated later in the week.

"It's been a very rough patch for markets and all of that centers around uncertainty over tariffs," said Art Hogan, chief market strategist at B. Riley Wealth.

A Reuters poll showed 91% of economists see higher recession risks due to Trump's shifting trade policies. HSBC also downgraded U.S. stocks, citing uncertainty around tariffs.

The S&P 500 recorded its largest weekly drop since September on Friday. On Monday, the Nasdaq fell more than 10% from its December high, on course for confirming a correction.

Since last week, the CBOE Volatility index has been at levels not seen since December.

Data on inflation, job openings and consumer confidence are due later in the week.

On Friday, investors took some comfort from Fed Chair Jerome Powell's comments that the economy was on a strong footing, but he also underscored the need for caution on lowering borrowing costs.

The Federal Open Market Committee will convene next week and traders expect policy rates to be left unchanged for the first half of this year, according to data compiled by LSEG.

U.S.-listed Chinese stocks such as Alibaba fell 3.1% and Bilibili lost 5%, after data from China heightened concerns about a recovery in the world's second-largest economy.

Crypto stocks such as MicroStrategy slid 10%, while Coinbase fell 9% and Riot declined 5.2%, tracking lower bitcoin prices.

Declining issues outnumbered advancers for a 2.83-to-1 ratio on the NYSE. On the Nasdaq, declining issues outnumbered advancers for a 2.98-to-1 ratio.

The S&P 500 posted three new 52-week highs and one new low, while the Nasdaq Composite recorded 10 new highs and 40 new lows.