408 MPs voted "for," while 226 votes were required to approve the ratification, 7 voted "against" and one deputy abstained.
The presidents of Russia, Belarus, Kazakhstan and Ukraine signed the agreement in Yalta on September 19, 2003.
The agreement envisages the merger of the signatory countries' customs territories, common principles heeding their economic systems, a free movement of commodities, services, capitals and manpower. The signatories intend to create a common market in the region by pursuing a single foreign policy, a coordinated tax, monetary-credit and currency-financial policies.
As advancing the document, Andrei Kokoshin, head of the Duma committee on CIS affairs and contacts with compatriots, said Ukraine's contribution was particularly important for stepping up the multilateral integration processes within the Commonwealth, although Ukraine was Russia's rival on a range of commodities.
Dmitry Sukhoparov, the president's representative for debates on the agreement and a deputy economic development minister, said, for his part, that the agreement would ensure a higher level for national producers and a growth in mutual commodity turnovers.
Under the agreement, the parties are expected to delegate some of national responsibilities to a coordinating body, which will address economic issues of mutual importance and work out common foreign trade and customs policies, which distinguishes the agreement from previous understandings.