Officials in Moscow and their allies in Abkhazia and South Ossetia all canceled meetings with international diplomats brokering the discussions, casting the future of the talks into question.
Kyiv has long taken a pro-Azerbaijan position vis-a-vis the conflict with Armenia. Now officials say that Armenia and Russia are using the blockade to try to steal attention from Ukraine.
Azerbaijan's blockade of the Lachin Corridor comes as it accuses Armenia of dragging its feet over the fate of another critical route, the would-be Zangezur Corridor.
Armenia says the plan amounts to a territorial claim, while domestic critics say it is meant as a nationalist distraction to the country’s real problems.
Azerbaijan has long opposed reestablishing air transit to and from Karabakh, though, and argues that it is Armenians who are refusing its offers to allow traffic on the road to resume.
With Azerbaijani demonstrators settling in for the long haul on the Lachin Corridor, Armenia is questioning whether Moscow is willing or able to end the standoff.
The territory has imposed price controls and rationing, and Azerbaijan has demanded that it be allowed to set up border and customs checkpoints on the road connecting it to Armenia.