US stock futures experienced a decline, and Treasuries also slipped, as market participants focused primarily on inflation risks. This heightened concern was driven by Brent crude oil surpassing the $100 per barrel mark. S&P 500 contracts saw a 0.3% decrease, while Nasdaq 100 futures also showed a downward trend.

The rise in Brent crude to over $100 per barrel, reaching as high as $101.55, is a significant psychological level for markets, according to Kathleen Brooks, research director at XTB trading group. This level increases costs for businesses and consumers, potentially weighing on economic growth and reinforcing fears of inflation.

Several analysts, including Samantha Dart, co-head of global commodities research at Goldman Sachs, noted that the surge in oil prices is a clear real-time signal for overall market sentiment. The $100 mark for Brent crude now feels like a highly achievable level, leading to increased speculation about central banks potentially raising interest rates to combat inflation.