ASTANA -- Russia, Belarus, Kazakhstan, and Kyrgyzstan have issued an ultimatum to Armenia, threatening to suspend its membership in the Moscow-led Eurasian Economic Union (EAEU) amid tensions over Armenia’s push to join the European Union.A joint declaration published on the Kremlin website claims that Armenian preparations for EU membership would endanger the “economic security" of the remaining member states.It demands that Armenia agree to hold a referendum “as soon as possible” on its plans, with the option being to either join the EU or stay in the EAEU.The move, agreed on at the EAEU summit in Astana, effectively transformed an event intended to showcase regional integration into an economic and political showdown.Armenian Prime Minister Nikol Pashinian skipped the meeting, sending a lower-level delegation led by Deputy Prime Minister Mher Grigorian.While widely interpreted by diplomats in Astana as a political boycott, Pashinian stated his absence was due to domestic campaign commitments ahead of Armenia’s June 7 parliamentary elections.Grigorian reportedly stated that Yerevan intends to maintain a constructive engagement with the EAEU but emphasized that future work must be rooted in the principles of "mutual respect, equal partnership," and national sovereignty.Growing Russian PressureThe ultimatum followed weeks of growing pressure from Moscow.Ahead of the meetings, Kremlin spokesman Dmitry Peskov had warned that Armenia’s pursuit of European Union integration was incompatible with the EAEU, calling them "mutually exclusive processes."