"The United States is conducting an Open Skies Treaty observation flight over Russia beginning Friday, February 22, and ending Saturday, February 23," the spokesman told in an email.
The flight is being conducted with a "treaty-certified OC-135B aircraft and cameras," he added.
It will be the first U.S. Open Skies flight since an impasse prevented standard treaty flights for all parties throughout 2018, the spokesman said.
The treaty, which went into effect in 2002, allows any of its nearly three dozen largely NATO and former Warsaw Pact member states to conduct unarmed surveillance flights to gather information about military forces.
The flight is being carried out with six Russian observers on board to monitor all phases of the flight, following treaty procedures.
Tensions between Russia and the U.S. intensified recently following Washington's decision to withdraw from the Intermediate-Range Nuclear Forces (INF) Treaty. The U.S.-based its decision on claims that Russia has violated the INF treaty by developing ground-based missile capabilities within the banned range of 500 to 5,500 kilometres.
Russia has denied the allegation and accused the US of violating the treaty by deploying missile systems in Eastern Europe.
Moscow responded to the U.S. withdrawal by saying it also will pull out of the decades-old bilateral treaty.