The announcment of the two parties' merger was made in a joint statement signed by both parties' leaders.
The Social Democratic Party, led by former presidential candidate Zharmakhan Tuyakbai, was registered in 2006, and Naghyz AK Zhol was registered earlier this year.
Recent amendments to Kazakhstan's constitution, including changes to the structure of parliament, have sparked speculation that early parliamentary elections will be held this year.
RFE/RL Central Asia Report
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