WASHINGTON (DTN) -- In the face of $6.53 national highway diesel, congressional leaders are offering a myriad of fuel cost solutions but toeing the fine line between supporting relief efforts and backing the war effort in Iran.

Weekly fuel data from the U.S. Energy Information Administration (EIA) pegs U.S. on-highway diesel fuel up 24 cents to $6.53 nationally as of Sept. 21. The Midwest region averaged $6.68, up 43 cents from a week ago.

The Lower Atlantic region measured the lowest diesel costs in America at $6.14 per gallon, which includes West Virginia, Virginia, North Carolina, South Carolina, Georgia and Florida. All prices reported indicate pre-tax values.

The cost of diesel today, "It is a direct result of clearly the Iranian conflict," said Agriculture Secretary Brooke Rollins said at a press conference on Monday. The costs facing farmers, "are not easy, and we know that." However, ensuring Iran never has a nuclear weapon takes precedent, she explained.

Diesel supplies remain tight, EIA forecasts. U.S. refineries had an operating capacity of 96.8% the week ending Sept. 11, limiting the ability to quickly boost diesel supplies. With diesel inventories projected to fall below 100 million barrels in September and remain below the five-year low through most of 2027, fuel has tightened and pushed diesel prices higher.

Republicans are now stepping up with solutions as harvest begins and the midterms near in November. The solutions range from an embargo on diesel exports to fuel subsidies for farmers.

In a post on X on Monday, Rep. Ashley Hinson said, "We need to use every option at our disposal to provide some relief from high prices."

She offered a slew of ideas including suspending the gas tax, pausing diesel exports, unleashing E15 everywhere we can, reinstating the $1-per-gallon biodiesel tax credit, and creating a diesel relief program to help our farmers and truckers being crushed by the high costs.

A community note was placed on her X post explaining how she voted four times against a resolution to bring immediate end to the war in Iran.

Her colleague, Sen. Chuck Grassley, R-Iowa, also said last week he supported an embargo on diesel exports.

"High diesel prices are killing farmers income," he said. "Big Oil is telling us we can't embargo diesel. If true, they still don't have to make the same profit off us farmers and truckers that they make in foreign sales."

The global diesel shortage is expected to persist as international production remains below last year's levels, encouraging continued U.S. exports, although improved crude oil flows from the Middle East could eventually boost refinery production in Asia and help ease diesel margins and prices over time, EIA explained in its forecast.

One of the first to comment, Sen. Roger Marshall, R-Kansas, faces one of the toughest Senate races. He addressed a letter with solutions to President Trump asking for targeted fuel relief aid for farmers and ranchers during harvest.

"Most producers made their planting, financing, and marketing decisions months ago, before this latest price spike, and they must now absorb substantial unplanned fuel costs during one of the most diesel-intensive periods of the year," the letter said.

Rollins said on Monday, "Expect an announcement very soon on some potential actions ... every tool in the toolkit is being evaluated right now."

FUEL OPPORRTUNITY: CALIFORNIA

Karen Ross, secretary of the California Department of Food and Agriculture, told DTN at the National Association of State Departments of Agriculture (NASDA) meeting last week that fuel costs factor directly into per-crop production costs.

"It adds to the cost of production, and then the quarrel becomes: Is it getting priced into (food costs)? Because we are especially in a highly perishable crop, we are price takers," she said.

A Midwest solution for California: E15. California Gov. Gavin Newsom signed SB 795 last week, paving the way for retailers to use existing E10 equipment for E15.

It's a move that increases fuel options for the most expensive fuel state in the country, while also giving corn states a place to send ethanol west.

E15 will need to develop a pattern of purchases and demand, Ross said.

She explained there are already mixed signals between electrification and renewable natural gas. "I think we also saw some signals from the current administration in California that aggressive getting off of fossil fuels has to have a realistic timeline to it," she said.

But "California, for all intents and purposes, is still very dedicated to trying to electrify our transportation as much as possible, but that's only going to go so far when there's only so many dollars in this space."

Ross, who grew up in Nebraska, compared the state's challenges with biofuels adoption in the early 2000s with California's situation today. "There was a whole adoption curve even in a state like Nebraska."

She said California will need to develop a similar adoption curve, potentially creating price differences and new opportunities for consumers.

See EIA's Short Term Energy Outlook: https://www.eia.gov/…

Senator Marshall's Letter: https://www.marshall.senate.gov/…

Jake Zajkowski can be reached at jake.zajkowski@dtn.com

Follow him on social platform X @jzajkow

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