The Central Asian country of Kyrgyzstan has joined the Eurasian Economic Union, a Russia-led trade bloc.

President Almazbek Atambayev on Thursday signed the law ratifying Kyrgyzstan's entry, joining Russia, Kazakhstan, Armenia and Belarus.

The union aims to create a single market for the free movement of goods and services over a total population of more than 180 million people, in a similar way as the 28-nation European Union.

Although it is nominally only a trade bloc, its economic heft could be used as a "soft power" political lever for Moscow.

Russia pushed hard for Ukraine to join the bloc, but opponents saw it as an attempt by Moscow to effectively reconstitute the Soviet Union. The issue was key to inciting protests that drove Ukraine's president out of office in 2014.