A US diesel export halt would tighten an already strained global middle-distillate market, with European and Asian buyers most exposed as cargoes bound for those regions are held at home. The likely near-term result is a split market: softer US domestic diesel prices against firmer overseas benchmarks, widening the gap between US and international product prices. Further out, lower US refinery runs would reduce crude demand at the margin while supporting gasoline and jet fuel. With Iran-war damage to Middle East refining already squeezing product supply, traders are likely to treat any announcement as a fresh source of volatility in refined products rather than a lasting fix.---Earlier:Trump weighs a US diesel export ban: how it would work and why analysts are waryFollow up ... Trump weighs diesel export ban: can a limited curb avoid the backlash?---Record diesel prices and a looming midterm vote are pushing the White House toward a 90-day export ban that its own energy secretary says would backfire, with a decision possibly only days away.Summary:The White House is preparing a plan to ban US diesel exports for 90 days says Politico, with the legal mechanism still being worked outTrump is reportedly inclined to announce by the end of the week, and Energy Secretary Wright told energy CEOs on Tuesday night a ban was likely within daysWright, Treasury Secretary Bessent and Interior Secretary Burgum have objected to a total ban; Wright publicly suggested voluntary changes to export flows instead, and a White House official dismissed the reportUS diesel averages around $6.50 a gallon, up about 90 cents in a month and more than $2.80 year on year, driven by the Iran war and Ukrainian strikes on Russian refineriesSenator Grassley's backing last weekend sparked a wave of farm-state Republican demands, with midterms less than seven weeks awayA ban would be the first US energy export restriction since 2015, and industry warns it could raise fuel prices later as refiners cut outputThe Trump administration is moving closer to a 90-day ban on US diesel exports, with the president said to be inclined to announce the measure before the end of this week, according to a Politico report citing five people familiar with the discussions. The plan is advancing despite resistance from senior cabinet members, refiners and some Republican lawmakers, and builds on the proposal we reported earlier this week and covered again in a follow-up post.Several signals point to momentum behind the move. Energy Secretary Chris Wright called energy chief executives on Tuesday night to tell them a 90-day halt was likely within days, according to an energy adviser to the president, who cautioned that the situation remained fluid. The adviser said the turning point came last weekend, when Iowa Senator Chuck Grassley, a leading voice for agriculture, publicly backed a ban over the damage high diesel prices are doing to farm incomes, prompting a wave of similar demands from farm-state Republicans. One oil industry executive who has spoken with senior White House officials said Trump appeared ready to treat any fallout as a problem for December, with political concerns over pump prices now outweighing more cautious voices.Opposition remains significant. Wright, Treasury Secretary Scott Bessent and Interior Secretary Doug Burgum have all objected to a total ban, according to people familiar with the talks. Speaking publicly on Wednesday, Wright argued that because refineries produce diesel alongside gasoline and jet fuel, blocking exports from the world's largest diesel exporter would eventually force run cuts once storage fills, lifting prices for other fuels. At a separate event he suggested exports would not stop outright, pointing instead to possible voluntary changes in where US diesel is shipped. A White House official dismissed the report as fake news, and the legal route for any ban is still being worked out.The pressure stems from prices. The average US diesel price stood at around $6.50 a gallon on Wednesday, according to AAA, up about 90 cents in a month and more than $2.80 from a year earlier. The Iran war that began in February has damaged Middle East refineries and reduced regional oil flows, while Ukrainian strikes on Russian refineries have further tightened supply.A ban would be the first restriction on US energy exports since a decades-old crude export ban was lifted in 2015. Diverting cargoes bound for Europe and Asia back into the domestic system could ease US prices in some regions at first, but refiners would likely cut output after losing a major export outlet, pushing prices higher later. One commodities economist warned a ban would worsen already severe global diesel strains and lift prices outside the US in the short term, while ultimately proving self-defeating. An external adviser to the administration also raised concerns that a ban could be repeatedly extended and set a precedent for government intervention in energy markets.With the midterm elections less than seven weeks away, the decision may rest with whoever is last in the room with Trump. Markets will watch whether any announcement this week takes the form of a full 90-day ban or the narrower, voluntary redirection Wright has described. This article was written by Eamonn Sheridan at investinglive.com.