The S&P 500 ended Tuesday's session near the flatline after President Donald Trump offered no exceptions to his Aug. 1 tariff start date.

The broad market benchmark inched down 0.07%, ending at 6,225.52, while the Nasdaq Composite added 0.03% and closed at 20,418.46. The Dow Jones Industrial Average slipped 165.60 points, or 0.37%, settling at 44,240.76.

Traders had trouble keeping up with the conflicting signals from Trump on trade. Trump on Monday pushed the tariff deadline to Aug. 1 from July 9. Later that day, he said that the new deadline was "not 100% firm."

However, on Tuesday, the president posted on Truth Social that there would be no change or extensions granted to the Aug. 1 date. The same day, Trump also announced a steep 50% tariff on copper imports.

Tuesday's action follows Monday's deep sell-off in which the Dow tumbled more than 400 points as Trump slapped 25% tariffs on South Korea and Japan. Trump hit at least 14 countries in total with new duties on Monday.

Investors are waiting for further clarity, with many expecting the ultimate tariff rates to not be as strict as what Trump has threatened.

"What we've seen since April has really been the markets getting past the idea that tariffs would have a particularly detrimental impact on growth, earnings, inflation, etc.," said Bill Merz, head of capital markets research at U.S. Bank Wealth Management. "Investor sentiment has shifted a lot in a very short period of time and become more optimistic, as we can see in equity market pricing and how we're right around all time highs across multiple indices."

On the upside, Nvidia advanced 1%, getting closer to a $4 trillion market cap. But banks helped weigh down the market, after HSBC adopted a "more cautious stance" on larger banks. Shares of JPMorgan and Bank of America shed 3%, while Goldman Sachs slipped nearly 2%.