The details of the economic integration program between Belarus and Russia provides for partial integration of the two economic systems since January 2021.
http://www.kasparov.ru/material.php?id=5D7FDD262A635
http://www.dsnews.ua/world/desyat-let-bez-malofeeva-pochemu-bolgary-zakryli-vezd-14092019220000
https://www.bbc.com/russian/news-49719476
http://www.ng.ru/world/2019-09-16/6_7677_world_03.html
http://www.ng.ru/cis/2019-09-16/5_7677_georgia.html
http://www.ng.ru/cis/2019-09-16/5_7677_belarus.html