US President Trump expected to unveil plan on red-dyed diesel on Monday; to ease use of tax-exempt variety of diesel

Dyed diesel is the tax-exempt grade reserved for off-road use, agriculture, construction, heating, kept chemically marked so tax authorities can distinguish it from on-road fuel and police the excise differential. Waivers relaxing that distinction have historically been issued as an emergency supply measure, typically after refinery outages or pipeline disruptions, and the mechanism is always the same: lifting the restriction lets dyed stocks flow into the road pool, which adds effective diesel supply without any change in refinery runs or imports. The effect has tended to show up first in the distillate crack and in regional diesel spreads rather than in the crude flat price, since crude itself is untouched by the measure. The open questions are the scope of any waiver, nationwide or regional, its duration, and whether it is framed as a price-relief measure rather than a response to an actual shortage, since the former signals an administration leaning on administrative levers to cap fuel prices. Worth watching is how the executive order or agency guidance is drafted, whether EPA and IRS enforcement rules are both suspended, and any parallel moves on the strategic reserve or export policy that would indicate a broader fuel-price effort.