A 5-year-old leak in a Russian module of the International Space Station (ISS) has worsened over time, and now NASA and Russia’s Roscosmos space agency are at odds over how dangerous the situation might be.

The leak is located in a Russian section of the station known as the PrK module, which connects Russia’s Zvezda service module to the main body of the space station.

NASA and the Russian space agency Roscosmos have known about the leak since at least 2019, but its underlying cause remains a mystery.

Since its discovery, astronauts have taken various measures to minimize its impact, including sealing the compartment when not in use.

According to a recent NASA report, the leak has intensified to the point where it jeopardizes the ISS’s goal of operating until 2030. Additionally, some NASA officials believe it could lead to a “catastrophic failure” of the station.

However, Roscosmos is refusing to fix the problem, downplaying the seriousness of the leak and insisting that it will not jeopardize future ISS operations, according to CNN and LiveScience.

The two space agencies have agreed to seal the leaking section if the rate of air loss becomes “unsustainable,” but have yet to reach a consensus on exactly what qualifies as an “unsustainable” rate.