Moscow has deplored Washington's decision of not joining the open skies treaty saying the US decision has allowed unarmed aerial flights over dozens of participating countries clouds the outlook for arms control discussions during next month’s planned summit between the presidents of the two countries.

The comments from the Russian side have been made a day after the US State Department informed Russia of the decision saying the accord "has been undermined by Russia's violations" and its failure to return to compliance.

"In concluding its review of the treaty, the United States, therefore, does not intend to seek to rejoin it, given Russia’s failure to take any actions to return to compliance. Further, Russia’s behavior, including its recent actions concerning Ukraine, is not that of a partner committed to confidence-building," the State Department said in announcing its decision.

The United States had withdrawn itself from the treaty in November under the Trump Presidency. The Open Skies Treaty came into force in 2002, allowing short-notice flights to monitor military activity. More than 30 nations participate in it.

Russian Deputy Foreign Minister Sergei Ryabkov expressed disappointment in relation to the US decision.

"It certainly does not make us happy. It is disappointing because the U.S. has missed another chance...to make a positive contribution to the task of strengthening security in Europe," the RIA Novosti news agency quoted Ryabkov as saying.