The US withdrew from the Treaty on Open Skies Sunday. The withdrawal only made official a May announcement from Secretary of State Mike Pompeo over a planned US exit from the treaty.

In the May announcement, Pompeo cited Russia’s failure to comply with the treaty as the reason for the planned exit. Pompeo said that the US would have considered remaining in the treaty had Russia also complied with the Treaty:

While the United States along with our Allies and partners that are States Parties to the Treaty have lived up to our commitments and obligations under the Treaty, Russia has flagrantly and continuously violated the Treaty in various ways for years. This is not a story exclusive to just the Treaty on Open Skies, unfortunately, for Russia has been a serial violator of many of its arms control obligations and commitments. Despite the Open Skies Treaty’s aspiration to build confidence and trust by demonstrating through unrestricted overflights that no party has anything to hide, Russia has consistently acted as if it were free to turn its obligations off and on at will, unlawfully denying or restricting Open Skies observation flights whenever it desires…These periodic and shifting violations highlight Russia’s willingness for many years now, to restrict or deny overflights whenever it desires. This strikes at the heart of the Treaty’s confidence-building purpose. … Make no mistake: Russia alone bears responsibility for these developments, and for the continued erosion of the arms control architecture. We remain committed to effective arms control that advances U.S., Ally, and partner security, that is verifiable and enforceable, and that includes partners that comply responsibly with their obligations. But we cannot remain in arms control agreements that are violated by the other side, and that are actively being used not to support but rather to undermine international peace and security. As noted, we may be willing to reconsider this decision if Russia demonstrates a return to full compliance with this confidence-building Treaty, but without such a change of course from the Kremlin, our path will lead to withdrawal in six months’ time.

Following the announcement, President-Elect Joe Biden, then-candidate for the Democratic presidential nomination, issued a statement on the withdrawal. Biden criticized the decision as short-sighted:

In announcing the intent to withdraw from the Open Skies Treaty, President Trump has doubled down on his short-sighted policy of going it alone and abandoning American leadership. With the world confronting the health and economic consequences of a global pandemic, the United States should be leading the international community, working with allies, and avoiding destabilizing actions. Withdrawal from Open Skies will have the opposite effect. The Treaty was negotiated and signed under President George H.W. Bush to build confidence and increase transparency in the Euro-Atlantic region. It allows the United States, NATO allies, Russia, and other European countries to fly over each other’s territories and take images to observe military forces and facilities. The transparency it provides is particularly important for countries that do not have their own satellite imaging capabilities.

Biden’s criticisms may signal a change in policy on the withdrawal with the incoming presidential administration.

The US entered into the Treaty on Open Skies in 1992. The treaty contained several measures to increase transparency between multiple countries over air military operations and reconnaissance during the Post-Cold War era.