Ukrainian military units are using commercial satellite imagery on frontline devices to make real-time battlefield decisions, according to The Wall Street Journal.

The technology is speeding up the kill chain and causing problems for Russian forces four years into the war.

The report comes two days after Ukrainian long-range drones struck an oil terminal in St. Petersburg and set it ablaze, sending smoke billowing over Russian President Vladimir Putin's hometown as the city hosted one of Russia's premier investment forums.

The drones flew more than 600 miles to hit the terminal in Russia's second-largest city, Ukrainian President Volodymyr Zelenskyy said on social media, a day after Moscow launched a major drone and missile attack on Kyiv and other Ukrainian cities.

The latest strikes are another setback for Putin, weeks after he downsized an annual Victory Day parade in Moscow because of fears of Ukrainian drone attacks.

Ukraine's own long-range attacks are aimed at diminishing Russia's oil production, which is a key source of funding for Moscow, and disrupting weapon production. Kyiv has repeatedly targeted oil facilities in St. Petersburg and nearby ports.

According to the Journal, over the past six months, small-team missions testing the technology operated by Colorado-based Vantor have shown that imagery from its commercial satellites can significantly improve the speed and accuracy of Ukrainian drone strikes.

By delivering geospatial intelligence directly to soldiers, the system has cut the time needed to locate and engage Russian targets by as much as 90%, according to the technology providers and people involved in the missions.

The imagery is paired with software that allows users to identify and analyze potential targets in detail.

The Journal said it is the first known case of unclassified commercial satellite imagery being delivered directly to individual soldiers.

The Associated Press contributed to this report.