Ambassador Klement is, besides assuming the function as the Permanent Representative of the European Union to the United Nations in Vienna, also a Special Advisor in charge of the nuclear implementation of the Joint Comprehensive Plan of Action (JCPOA) in the European External Action Service. He was involved in the negotiations on the Iranian nuclear issues since 2004. 

Ambassador Klement has more than 20 years of experience in the nuclear policy and nuclear non-proliferation field, working in different European Institutions, as well as in the International Atomic Energy Agency (IAEA). He was also Head of Unit Euratom Co-ordination, Legal Matters and International Relations at the Directorate-General for Energy, European Commission. 

Ambassador Klement holds a Doctoral degree in International Law and a Doctoral degree in Physics, both from the University of Vienna, Austria. 

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    Ambassador Stephan Klement, Head of Delegation to the International Organisations in Vienna and assumed the post of the EU Permanent Representative to the UN Organisations in Vienna, IAEA and CTBTO

    Ambassador Stephan Klement, Head of Delegation to the International Organisations in Vienna and assumed the post of the EU Permanent Representative to the UN Organisations in Vienna, IAEA and CTBTO.

A message from Ambassador Stephan Klement, Head of Delegation

Dear Visitor, 

Thank you for your interest in the work of the Delegation of the EU to the International Organisations in Vienna. It is my honour to welcome you to our website, which aims to provide you with up-to-date information about how the Delegation works to present, explain and implement the EU's foreign policies within the Vienna-based multilateral environment. 

The work and activities of the EU on the international scene, and subsequently those of our Delegation here in Vienna, are guided by the principles enshrined in the Treaty of Lisbon: advancing democracy, the rule of law, universality and indivisibility of human rights and fundamental freedoms, respect for human dignity, the principles of equality and solidarity and respect for the United Nations (UN) Charter and international law. 

We created a European External Action Service to ensure that when we speak, our voice is heard. And when we engage, our actions make a difference. Our citizens know that in the face of global issues we are more effective together. But we are mindful that for Europe to make progress towards its ambitious goals, it needs partners. Therefore, our role is to coordinate with the EU Member States, engage with other countries that are members of the organisations, and work to further build on our strengthened cooperation with the United Nations, the UN related bodies or specialized agencies established in Vienna, the Organisation for Security and Co-operation in Europe (OSCE), as well as civil society organisations who share the aforementioned fundamental values and principles. 

Our partners in the Vienna-based International Organisations play a key role in the implementation of numerous projects around the world that aim at fostering peace and security, safeguarding the global nuclear non-proliferation regime, combatting international drug and crime groups, fighting corruption and human trafficking and promoting alternative development. We are also working to actively resolve conflicts in the OSCE region, such as the crisis in and around Ukraine, promote cyber security, enhance openness and transparency of military activities, promote democratisation and human rights, including of persons belonging to national minorities, and help civil society and independent media to voice their concerns. 

Browsing through our website, you will find information on the many ways the EU engages with partners in the Vienna-based Organisations and how it supports these Organisations, either politically or financially, in order to allow them to develop and implement their goals and commitments. Further information on EU policies and activities can be easily accessed through the Europa Server

I hope that you will find our website useful. Your comments and suggestions are most welcome and should be sent by email to

Enjoy your visit! 

Ambassador Stephan KLEMENT