Skip to navigationSkip to main contentSkip to right columnADVERTISEMENTBy Anna SzymanskiFri, September 11, 2026 at 12:45 PM GMT+2 7 min readBy Anna SzymanskiSept 11 (Reuters) - As summer fades, so have hopes for a quick resolution to the U.S.-Iran conflict, as tit-for-tat strikes, new threats in the Red Sea, and President Donald Trump's comments about the war lasting through November have all helped push crude prices back above $100 a barrel for the first time since July.This has contributed to a new surge in global borrowing costs, with the U.S. benchmark 10-year yield now nearing 5%, as markets anxiously await today's U.S. CPI inflation report and next week's Federal Reserve meeting, where uncertainty about the policy outcome is the highest in years.School is definitely back in session.When the summer began, Tehran and Washington had agreed on a memorandum of understanding, the Strait of Hormuz was set to reopen, and oil prices were falling rapidly.Fast forward to the second week of September, and that optimism is gone. The U.S. reported destroying five Iranian oil tankers on Tuesday, and Iran's Revolutionary Guards responded by firing ballistic missiles at a base in Jordan, as well as attacking 10 ships near the Strait of Hormuz, including two U.S. vessels.Perhaps most worryingly, the Iran-aligned Houthis, who attacked Saudi cities earlier in the week, seized control of Yemen's port city of Mocha on Thursday and advanced down the Red Sea coast to strategic islands. This threatens the Bab el-Mandeb Strait, another key shipping route that Saudi Arabia has relied on to export oil since the effective closure of Hormuz in February.Amid this backdrop, global oil prices, which had been inching up for weeks, finally broke through the psychologically important $100/bbl level on Wednesday, with Brent settling up 6% on Thursday at nearly $108/bbl, before paring some of these gains early on Friday.The spike in energy prices raised inflation fears and rate-hike expectations, pushing up already-elevated government borrowing costs across developed markets. The benchmark 10-year U.S. Treasury yield hit its highest level since 2023, rising above 4.9% on Thursday, while the 30-year yield reached a nearly two-decade high above 5.38% and the 2-year yield jumped to almost 4.6%, its highest point in 14 months.The bond ructions in the U.S. also reflected investors' disappointment with the limited size of Treasury Secretary Scott Bessent's plan to buy back longer-dated bonds, details of which were announced on Wednesday.The energy market's current dynamics may keep the bond market on edge for some time, as today's elevated oil prices reflect more than just supply-and-demand fundamentals, which are rather murky. Traders, energy companies and government officials all still disagree about exactly how much oil is exiting the Gulf.Terms and Privacy PolicyEU DSA contactPrivacy & Cookie SettingsMore Info