When did the US withdraw from the Open Skies Treaty?

In April 2020, it was reported that Secretary of State Mike Pompeo and Secretary of Defense Mark Esper had agreed to proceed with U.S. withdrawal from the Treaty on Open Skies. On May 21, 2020, President Trump announced that the United States would be withdrawing from the treaty due to alleged Russian violations. On 22 May 2020, the United States submitted a notice of withdrawal from the Treaty on Open Skies. Senate Democrats questioned the legality, wisdom, and appropriateness of the planned withdrawal so close to the 2020 United States presidential election. The U.S. said it would share some of its intelligence and reconnaissance information with European allies to make up for any loss of critical information from the end of the Treaty. On 22 November 2020, United States official sources—including U.S. Department of State websites, Secretary of State Mike Pompeo, and the National Security Council’s official Twitter account—announced that the six-month period was over and the U.S. was no longer a party to the Treaty.