The Intermediate-Range Nuclear Forces Treaty, or INF Treaty, has been the subject of diplomatic debate between the United States and Russia for months now. Although the agreement may be lengthy, the nuts and bolts of it are simple: It bans the development or use of nuclear or conventional missiles (as well as their associated launch platforms) that have ranges between 500–1,000 kilometers (310–620 mi) in the “short range” category and 1,000–5,500 km (620–3,420 mi) categorized as “intermediate” range.

At one time or another, the agreement has come into question by both Russian and U.S. leaders, but the current predicament is a bit different. According to U.S. intelligence, Russia developed and built a new missile platform that directly violates the language of the treaty. This makes the treaty all but useless to the United States, which must also compete with other non-signatory nations that have no compunction about developing similar platforms themselves (e.g. China). In effect, if Russia doesn’t follow the treaty, then America is simply barring itself from developing the same sort of weapons being fielded by its competitors. As a result, the Trump administration has signaled America’s intention to withdraw from the treaty unless Russia verifiably destroys their new platform.

Russia contends, however, that their new missile does not violate the terms of the treaty and is, instead, an updated version of an older platform built with a specifically reduced range. The 9M729 cruise missile, according to Moscow, is nothing more than an updated 9M728. They claim that, although it’s some 20 inches longer than its predecessor, its range is actually less than that of the legacy system by a bit more than six miles. According to Russia, the added length can be attributed to a “modernized onboard correction system” meant to improve the missile’s accuracy, leaving the fuel compartment identical in size to the missile’s predecessor.

Of course, with a slightly more efficient engine, the missile could feasibly travel farther on the same amount of fuel as the older platform, but the thing is, no one can even be certain that Russia is telling the truth about the size of the fuel supply in the first place. With that in mind, Russia took the unprecedented step of offering what they call “transparency” regarding the new missile. They have offered to invite journalists from all over the world to come see the missile themselves so they can confirm its technical details.