The following is the April 7, 2021 Congressional Research Service Insight Report, The Open Skies Treaty: Background and Issues.
From the report
The United States announced its withdrawal from the Treaty on Open Skies on May 22, 2020; this withdrawal took effect on November 22, 2020. The United States no longer participates in flights or shares data collected by others. Russia also announced its plans to withdraw, while beginning the domestic procedures for withdrawal on January 15, 2021. It has...
https://news.usni.org/2021/04/08/report-to-congress-on-open-skies-treaty