Wall Street futures and the dollar experienced a downturn as confusion surrounding U.S. tariffs revived a "sell America" sentiment. Confidence in the AI sector faces a critical test this week with earnings expected from tech giant Nvidia.

Gold prices rose and oil eased ahead of crucial U.S.-Iran talks, with the potential for military action if a nuclear deal falters. The market faces significant uncertainty after the U.S. Supreme Court invalidated President Trump's emergency tariffs. Subsequent announcements of new tariff rates, fluctuating between 10 and 15 percent, have left officials and markets scrambling.

"The tariff landscape is now more uncertain than before, uncertainty is not good news for any economy or market," stated Rodrigo Catril, a senior FX strategist at NAB. He warned of a potential cycle of shifting tariff announcements and reversals.

Asian markets showed mixed results. MSCI's Asia-Pacific index outside Japan gained 0.8 percent. South Korea's stock market extended its bull run with a 1.2 percent rise, reaching all-time highs, while Taiwan also hit a record peak.

In Europe, futures for the EUROSTOXX 50 and DAX indices fell 0.5 percent, and FTSE futures dropped 0.1 percent.

S&P 500 futures declined 0.7 percent, and Nasdaq futures dropped 0.9 percent. Investors are anticipating Nvidia's earnings report, a significant event as the company represents nearly 8 percent of the S&P 500 index. Nvidia is projected to report a 71 percent increase in earnings per share, with potential share price volatility of at least 6 percent following the announcement.

The U.S. Treasury market was impacted by the tariff news, raising concerns about potential revenue repayments and a widening fiscal deficit. While Japanese markets were closed, futures indicated a downtick in 10-year Treasury notes.

The dollar weakened against the Japanese yen, falling 0.6 percent to 154.06, and gained 0.4 percent against the euro, reaching $1.1826. The dollar also slid 0.6 percent versus the Swiss franc to 0.7716. Bitcoin saw a significant drop of 4.6 percent, trading at $64,478.

In commodities, gold saw a 1.0 percent increase to $5,156 per ounce, and silver gained 3.2 percent to $87.25 per ounce. Oil prices were volatile, with Brent crude down 1.1 percent to $70.94 a barrel and U.S. crude down 1.2 percent to $65.71 per barrel.