Proliferation Security Initiative (PSI)


The Proliferation Security Initiative provides a framework for a number of countries to cooperate to prevent the proliferation of weapons of mass destruction. Germany is a co-founder of the initiative, which was launched in 2003.

The Proliferation Security Initiative provides a framework for a number of countries to cooperate to prevent the transport and transfer of weapons of mass destruction (proliferation). Germany co-founded the initiative, which was launched in 2003 and goes back to a proposal put forward by the United States.

PSI Logo

Despite relevant bans, individuals as well as states and non state actors have repeatedly succeeded in acquiring the necessary technology for the manufacture of weapons of mass destruction. In many instances those involved have taken advantage of global trade to circumvent national controls and conceal the true nature of their activities.

Through network building and regular training exercises, the PSI aims to improve cooperation on the interdiction of suspect transfers by land, sea or air of items that could be used to manufacture nuclear, chemical or biological weapons and delivery systems. The PSI is intended to effectively supplement existing export control regimes and non-proliferation agreements. All PSI activities are fully consistent with applicable international and domestic law.

In 2003, the endorsing states agreed on shared Interdiction Principles.

Statement of Interdiction Principles (engl.) PDF / 12 KB

As of today 105 countries have expressed their support for the Initiative’s goals. A core group of 21 member states meet once or twice a year as the Operational Experts Group (OEG). There are also regional meetings, and international training exercises are conducted to practice preventing the transport of goods relevant to proliferation.

In June 2015, a seminar was held in Frankfurt am Main, launching the Franco-German Mediterranean Initiative intended to extend the PSI to the countries on the southern Mediterranean coast. Suvsequent events were organized by France in October 2015 and Italy in November 2016.

Perhaps the best-known example of a successful interdiction operation was the seizure in October 2003 of the vessel BBC China and its cargo of gas ultracentrifuge casings intended for Libya’s nuclear weapons programme. In the wake of this incident, Libya terminated its military nuclear weapons programme.

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