A treaty expiring next year could spell trouble in space for two of the world’s biggest countries.

The New Strategic Arms Reduction Treaty (New START) – which will expire in February 2021 – is a pact between the U.S. and Russia to limit strategic offensive arms.

According to the treaty, the U.S. and Russia may agree to extend the terms for a period of not more than five years.

However, a new study conducted by the Aerospace Corporation’s Center for Space Policy and Strategy, said prospects for New START’s extension are “dim,” which is likely to have “negative implications.”

“When these instruments for managing strategic relationships erode, are absent, or are misapplied, the likelihood for miscommunication, misunderstanding, and miscalculation leading to conflict increase,” researchers wrote. “There is less crisis stability and, in turn, less strategic stability.”

One of the biggest problems would be the absence of national technical means of verification – or monitoring techniques like satellite imagery – to verify, for example, that the other side is not building up armaments.

In lieu of a new treaty, researchers say the best-case scenario is that both sides practice noncodified, mutual restraint. However, that arrangement still could lead to problems in times of crises.

Worst case is that there is no mutual restraint whereby strategic nuclear stability could be threatened.

“The stability of the space domain deteriorates severely due to the absence of mutual restraint and the degradation of existing processes for developing international norms of behavior for space,” the report said. “Current threats to stability in the space domain are greatly exacerbated, resulting in its full destabilization.”

Researchers say the abandonment of the treaty may also have effects beyond just the U.S. and Russia – it could cause international efforts to create norms for responsible conduct in outer space to lose steam.

Aggregate limits of New START, which went into effect in Feburary 2011, include 700 deployed intercontinental ballistic missiles (ICBMs), deployed submarine-launched missiles (SLBMs) and deployed heavy bombers equipped for nuclear armaments; 1,1550 nuclear warheads deployed on ICBMs, SLBMs and deployed heavy bombers equipped for nuclear armaments; 800 deployed and non-deployed ICBM launchers, SLBM launchers and heavy bombers equipped for nuclear armaments.

Space has become a focal point for President Trump after he recently designated the Space Force the sixth branch of the U.S. military. The goals are not only to secure American dominance in space but also to promote national security and to increase warfighting capabilities. Trump has said that the U.S. is facing competition from both Russia and China in space, which he called the “world’s newest war-fighting domain.”