Jet fuel, a kerosene-based product akin to diesel fuel, has roughly doubled in price since last April across the U.S., according to S&P Global Commodity Insights, while gasoline has risen about 45%, the Wall Street Journal reported. A fall in exports of Russian diesel in recent weeks has driven Western refiners to shift resources from jet to diesel production, leaving jet fuel undersupplied, S&P Global Commodity Insights analysts said. Rising jet-fuel costs threaten to strain airlines’ profitability just as resurgent travel demand promised relief from the pandemic’s toll on the industry. They are also frustrating passengers who face eye-watering ticket prices as airlines pass on high fuel prices to their customers. The war in Ukraine has lifted energy prices across the board this year as the West shuns Russia’s oil exports, denting world-wide supply. Diesel and jet fuel have seen some of the sharpest price increases. Demand for diesel stayed relatively strong throughout the pandemic, and Europe relied on Russian sources for it before the war. The two fuels are often produced in the same facilities, so a diesel crunch squeezes jet-fuel markets. An uptick in airline travel as the pandemic abates is stretching supplies further. Fuel prices and their upward pressure on airfares helped make airline travel one of the fastest-rising components of the consumer-price index, a measure of inflation, last month. (Subscription required.)