It says the blockade could destabilise the country and lead to a humanitarian catastrophe.
A report published on the website of the Tajik embassy in Moscow accused Uzbekistan of blocking vital rail freight and cutting gas supplies.
Relations between the countries have deteriorated over a hydro-electric dam that Tajikistan is building.
Uzbekistan fears the dam will restrict water supplies to its main cash crop, cotton.
In its strongly worded statement, the Tajik embassy in Moscow accused the Uzbek authorities of deliberately creating the blockade.
The Uzbek government has cut natural gas supplies to Tajikistan. It says it can no longer supply gas to the Tajiks as it has to meet growing demand from its main partner, China, but the amount Tajikistan needs is small by comparison.
The BBC’s Rayhan Demytrie says the two countries have historic and cultural ties but relations are poor.
No flights operate between the two capitals and citizens of both countries require visas to cross the border.