In a further sign of deteriorating relations between the U.S. and Russia, the U.S. claimed that Russia is violating the Open Skies Treaty. The Wall Street Journal reported the U.S. would restrict Russian military flights over U.S. territory, in response to Moscow's new restrictions on U.S. observation flights over its western enclave region Kaliningrad, which have now been limited to 500 km (when the territory under surveillance is more than double that expanse. It is worth noting that in June 2017, the U.S. informed the Open Skies Consultative Commission (OSCC) that it has "formally determined Russia to be in violation of its Open Skies Treaty obligations." Russia expects the U.S. to impose restrictions on Russia's flights under the Treaty on Open Skies as of January 1, 2018.
Deputy Foreign Minister Sergey Ryabkov commented: "Apparently, things are coming to taking certain retaliatory measures by the Russian side… But before we announce something on this, we should analyze the situation together with our military and come to an expert finding and look at what form to respond to the Americans… But there will be a response, I have no doubt about this." Ryabkov then stressed: "We believe that this treaty gives no unilateral advantages to any party. It is a mutually beneficial, crucial and valuable document worth preserving, but the United States has demonstrated by its actions that it prefers to proceed along the path of pressures. Naturally, no decisions they would like to see can be worked out under pressure and no unilateral concessions by us are possible in principle."
Mikhail Ulyanov, head of the Russian Foreign Ministry's Department for Nonproliferation and Arms Control, called for compromise since the agreement is a complex one that is subject to differing interpretations. 
The following are excerpts from Russian MFA spokesperson Maria Zakharova's briefing that addressed U.S. concerns about Russia's implementation of the Open Skies Treaty:
In 2016, the State Department published the following fact sheet: "Since the Treaty entered-into-force in 2002, the United States has flown nearly three-times as many flights annually over Russia as Russia flies over the United States. The Open Skies Treaty flight plans (2002 – 2016) show 196 bids by the United States (for flights over Russia) and 71 bids by Russia over the United States. Further, the United States can request copies of the imagery from other State Parties’ flights over Russia. Since 2002 there have been over 500 such flights by other state parties over Russia." (Source: Key Facts About the Open Skies Treaty)
Russia's MFA Spokesperson Zakharova: 'Why Are They Doing This? [Washington] Probably Wants To Distract Public Attention From The Really Serious OST Violations By The United States'
Zakharova rebuts U.S. charges on Open Skies (Source: Youtube.com)
In her weekly briefing, Russia's Foreign Ministry Spokesperson Maria Zakharova made the following comments in response to reported U.S. intentions to limit Russian observation flight over American territory. :
"We have taken note of numerous media reports about the United States' intention to take steps to limit Russian observation flights over American territory in response to Russia's alleged violations of the Open Skies Treaty (OST). I will tell you about the alleged violations and our response to these allegations.
"As far as we can see, Washington blames Russia for three alleged violations.
"First, Russia has imposed restrictions, allegedly unlawfully, on observation flights over the Kaliningrad Region. According to the United States, this precludes effective observation of Russia's territory during the approved number of flights. Moreover, NATO countries have accused Russia of a desire to 'conceal' military facilities near Kaliningrad from Open Skies cameras.
"It is much simpler than this, though. Some of our partners, who have the right to make observation flights at a maximum distance of 5,500 kilometers, used this right over the Kaliningrad Region, flying over it far and wide, which created problems in the limited airspace of the region and hindered the operation of Khrabrovo International Airport. [Flight safety is the major provision in the treaty allowing signatories to deny overflights] We did not manage to convince our partners to show a reasonable degree of restraint. This is why we had to minimize spending by restricting the maximum flight distance over the Kaliningrad Region to 500 kilometers. This is not contrary to the OST or the signatories' subsequent decisions. I would like to point out that this has not changed the total flight distance of 5,500 km and hence coverage of Russia's territory. The flight range of 500 km over the Kaliningrad Region is sufficient for observing any part of the region, even the most distant areas, during observation flights. In other words, this restriction has not affected observation effectiveness.
"By the way, the United States did likewise when it restricted the distance of observation flights over the U.S. exclave, Alaska, which start on the continental part of American territory.
"It gives me pleasure to listen to our American colleagues' complaints, considering that they have assumed their positions only recently and are not aware of many details. We are willing to help them clarify the situation. They only need to ask.
"Second, Russia has been accused of the unlawful denial to permit observation flights in the 10 kilometer border area of the so-called Georgian regions of Abkhazia and South Ossetia.
"This problem is rooted in political differences. The Treaty says that 'the flight path of an observation aircraft shall not be closer than ten kilometers from the border with an adjacent State that is not a State Party.' To Russia and several other states, Abkhazia and South Ossetia ceased to be 'Georgian regions' back in 2008 (I am saying this for those of our U.S. colleagues who assumed office only recently). They are sovereign states and hence the OST provision I have cited is fully applicable to them. The reasons for this are common knowledge. If some of our partners cannot accept the new political realities in the Caucasus, it is their problem, but definitely cannot be interpreted as an OST violation.
"By the way, Georgia has closed its skies to Russian observation flights for political reasons, which is a clear and gross violation of the key OST provision. However, our Western partners have closed their eyes to this and have not criticized Georgia for this.
"Third, Russia has been accused of overusing the force majeure provision to change the coordinated plans of observation flights due to flights made by the country's leaders in close proximity to the planned paths of observation flights.
"This is the most absurd allegation of all, because we have used the above provision only once since the OST was adopted in 2002, several years ago. We subsequently discussed this matter with our partners and it was agreed that the priority for state leaders' flights, which other states party also observe, can be coordinated without invoking the force majeure provision. The matter seemed to have been settled and laid to rest. However, they are still tempted to present as many complaints against Russia as possible even if the substantiation is completely nonsensical.
"Why are they doing this? On the one hand, they probably want to distract public attention from the really serious OST violations by the United States, its allies and wards. There have been very many such violations, enough for a whole page. The most flagrant of them concern direct or indirect restrictions on observation flights over the entire territory or whole regions of some member states. However, Washington prefers not to notice these violations.
"Another reason could be the negative attitude of some Congressmen and the U.S. military and political establishment to the Open Skies Treaty itself.
"Anyway, Washington's attitude bodes ill for the OST, as we have told our partners.
"Regarding media reports about the potential countermeasures, which the United States is considering to complicate Russian observation flights over U.S. territory, we will analyze them, including for compliance with the OST. We will analyze them and then we will take a decision on appropriate response measures, because nobody has cancelled the principle of reciprocity in international affairs. It is far from clear what the United States stands to gain. Anyway, Washington will definitely not see any unilateral advantages.
"I would like to say in conclusion that confrontation is not our choice. We suggest that our American partners stop before taking the plunge into yet another chasm of measures and countermeasures, stop before the measures they have announced come into effect and instead launch a politically impartial search for mutually acceptable solutions to OST issues. This, of course, should be based on respect for the concerns and interests of all parties rather than only the United States."
 "The Treaty on Open Skies establishes a regime of unarmed aerial observation flights over the territories of its signatories. The Treaty is designed to enhance mutual understanding and confidence by giving all participants, regardless of size, a direct role in gathering information through aerial imaging on military forces and activities of concern to them. Open Skies is one of the most wide-ranging international arms control efforts to date to promote openness and transparency in military forces and activities." (State.gov)
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