Iowa Sen. Chuck Grassley urged President Trump to impose an embargo on diesel exports as the US national average reached $6.505 a gallon on September 21, according to AAA, after crossing $6 around September 10-11. Prices were about 60% above a year earlier, while Iowa’s average was about $6.29. US inventories fell to 106.3 million barrels, roughly 13% below the five-year average, ahead of the fall harvest. Grassley said high fuel costs are eroding farmers’ incomes and hurting truckers. The proposal has intensified Republican debate over export restrictions, with Senate Majority Leader John Thune open to exploring a ban and Interior Secretary Doug Burgum saying it would not lower prices. Disruptions linked to the US-Israeli conflict with Iran, including shipping problems through the Strait of Hormuz, and Ukrainian attacks on Russian refineries have tightened supply. Brown University estimated higher diesel prices added more than $46 billion to US consumer fuel costs since the Iran-related conflict began.