U.S. stock markets declined further on Monday as rising oil prices added to growing concerns about inflation and economic stability. The price of Brent crude surged 2.7 percent, reaching $90.87 per barrel, amid ongoing uncertainties linked to tensions surrounding Iran and their impact on global oil supplies.

Since last month, Brent crude prices have fluctuated significantly, swinging between $72 and $102 per barrel. Market volatility has largely been driven by speculation over whether the United States and Iran might reach an agreement to allow unrestricted passage of oil tankers through the Persian Gulf, a key route for global crude shipments. These hopes have waxed and waned, contributing to the price oscillations.

Monday’s increase in oil prices coincided with a rise in U.S. Treasury yields. The yield on the 10-year Treasury note climbed to 4.72 percent, up from 4.68 percent at the close of trading on Friday. This represents a considerable jump from pre-conflict levels near 3.97 percent, reflecting investor concerns that sustained higher energy costs may intensify inflationary pressures.

Higher inflation expectations have increased the likelihood that the Federal Reserve will implement further interest rate hikes in an effort to temper rising prices. While such monetary tightening can help rein in inflation, it also tends to slow economic growth by raising borrowing costs for businesses and consumers.

Investors are thus grappling with the dual challenges of persistent geopolitical risks affecting oil supply and the resulting economic implications of an elevated interest rate environment. The interplay between these factors remains a key focal point for financial markets as they navigate the evolving landscape shaped by the ongoing conflict involving Iran.