Dalal Street is poised to open Monday amid fresh uncertainity after US President Donald Trump announced increasing temporary global tariffs on nearly all imports, from 10% to 15%. The move came just a day after the US Supreme Court struck down his earlier broad tariff programme, leaving investors questioning whether trade tensions are returning.Earlier this week, Supreme Court had ruled that Trump exceeded his authority by imposing wide-ranging tariffs under an economic emergency law. Markets initially welcomed the verdict, with the Nifty surging on relief that a significant trade-related risk had been removed.Yet the reprieve was short-lived as just hours later, Trump imposed a 10% tariff under a separate legal provision, and on Saturday. After the first increament, he further hiked it to 15%, the maximum allowed under Section 122 of US trade law. This section permits tariffs of up to 15% for 150 days, after which, any extensionmust be approved by Congress.Trump also indicated that the administration may explore other legal avenues, including national security or unfair trade measures, to continue imposing import duties during this period.For investors, the concern lies less in the specific rate than the unpredictability. Nilesh Shah, MD of Kotak Mahindra AMC, said, “The Street expectation is that the US will use various provisions of law to keep tariffs almost unchanged. Any change will be short-term and, hence, unlikely to impact market direction materially.”Nonetheless, short-term volatility is expected. Sudeep Shah, Head of Technical and Derivatives Research at SBI Securities, told ET, “An important aspect to monitor is the uncertainty surrounding the approximately $175 billion collected under tariffs over the past year and the potential implications of refund claims. That said, the situation remains fluid. Any fresh statements or alternative tariff actions under different presidential authorities could reintroduce volatility in the near term.”The timing is critical for India as equities have already been pressured by US Federal Reserve policy uncertainty and weak IT stocks. Earlier this month, India and the US had reached an interim trade understanding that lowered reciprocal tariffs on Indian goods to 18%, while India agreed to reduce certain tariffs and non-tariff barriers on US imports.Sectors that focus on exports like IT, pharmaceuticals, textiles, and auto components may react sharply to concerns over margins or demand. However, if markets view the 15% cap as temporary and largely in line with expectations, losses are expected to remain limited.(Disclaimer: Recommendations and views on the stock market, other asset classes or personal finance management tips given by experts are their own. These opinions do not represent the views of The Times of India)