[International Finance Briefing] Brent crude plunges 5.9% on hopes for US-Iran negotiations... S&P 500 posts biggest gain since early April

Brent crude plunged 5.9% to $92.6 a barrel as growing expectations of a diplomatic resolution to the U.S.–Iran conflict triggered a sharp reversal in oil markets. The de-escalation signals from Iranian President Pezeshkian and U.S. President Trump also fueled a broad rally in U.S. equities, with the S&P 500 posting its largest gain since early April, led by technology stocks. The drop in oil prices eased inflation concerns, though Federal Reserve officials pointed to resilient demand and elevated prices in signaling that further rate hikes may be needed. The moves matter because they reflect markets repricing geopolitical risk and energy-driven inflation in real time. What to watch next is whether U.S.–Iran negotiations translate into concrete progress, and whether the oil decline is sustained enough to shift the Fed's rate path.