And they formally launched a joint study for a trilateral free-trade agreement with a target completion date in 2012.

三国正式启动了一项有关三方自由贸易协定的联合研究，研究的完成日期定在2012年。

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The British defense journal Jane's Intelligence Digest reported in the spring that the Russian sale of highly advanced S-300PS surface-to-air missiles to Belarus may windup being secretly transferred to Iran as part of a trilateral agreement between Moscow, Minsk, and Tehran.

CENTERFORSECURITYPOLICY: The nexus of evil

Such an alliance, however, cannot be built on a trilateral peacekeeping agreement including Syria.

CENTERFORSECURITYPOLICY: Center for Security Policy | What hazards along the road to Damascus? Mission impossible