Russia said it needed to understand the European Union's position after the Armenian government backed a bill that would kickstart the country's EU accession process, Reuters reported.
Kremlin spokesman Dmitry Peskov said it was impossible for Armenia to be a member of both the Eurasian Economic Union and the EU.
In recent years, Armenia has deepened its ties with the West at the expense of its close ties with Moscow, which has been criticized for failing to protect it from long-time rival Azerbaijan.