The Collective Security Treaty Organization (CSTO) has enough capacities to respond to any potential threat coming from NATO as it continues to expand eastward, the bloc’s Secretary-General Stanislav Zas of Belarus stressed on Sunday. 
 
"We have enough forces and means to react to potential threats that are bound to emerge in this situation," Zas told Belarus 1 channel in a comment on NATO’s Nordic expansion.
 
But the bloc’s Secretary-General added that a CSTO buildup was "not on the agenda at the moment."
 
Zas warned that the CSTO - the military alliance including Armenia, Belarus, Kazakhstan, Russia, and Tajikistan - sees the addition of Finland and Sweden to NATO as a source of tension.
 
"Of course, we see this expansion as a prerequisite for tension and further militarization in the region. It will not bolster security, including in NATO countries," he said.

It is noteworthy that despite widespread support from other allies, notably the United States, Turkish President Recep Tayyip Erdogan stated on Saturday that Turkey would not look "positively" on Sweden and Finland's NATO ambitions until its terror-related worries were addressed.

Turkey has long accused Nordic nations, particularly Sweden, of housing banned Kurdish militants as well as supporters of Fethullah Gulen, the US-based preacher wanted in connection with the attempted 2016 coup.

Since NATO choices require unanimity, Erdogan's ultimatum poses a significant potential barrier to the membership of the formerly militarily non-aligned Nordic nations.