The UK’s future security relationship with the EU will be of the utmost concern in light of Brexit. This will likely mean consistency in its foreign policy approach to Russia. That is not to say that constructive dialogue is not a genuine shared interest, but it will be in small measure at first rather than any post-Brexit grand agreement.
Russia believes that it only makes sense to develop relations with major European Union powers, as it counts on the further weakening of the EU. But European institutions are designed so that large countries are unable to dominate them. Russia needs to change its attitude to small EU countries because it is they that will strive for greater unity in the spheres of defense and security.
Relations between Russia, Europe, and the United States are in flux as none is able or wants to maintain what it once had. An attempt to revive the Cold War paradigm has failed, and a new framework of relations has not formed. This state of uncertainty will most likely endure until each player achieves a measure of domestic stability.
Russia’s new relationship with the EU could be that of a hybrid vehicle that can run either off the old internal combustion model of East-West geopolitical division or off the new system of global, regional, and sub-regional regimes that preserve and expand the “shared spaces” of Russia and Europe.