« back

Mutual defence clause

« Back to Glossary Index

The Treaty of Lisbon strengthens the solidarity between EU countries in dealing with external threats by introducing a mutual defence clause (Article  42(7) of the Treaty on European Union). This clause provides that if an EU country is the victim of armed aggression on its territory, the other EU countries have an obligation to aid and assist it by all the means in their power, in accordance with Article  51 of the United Nations Charter.

This obligation of mutual defence is binding on all EU countries. However, it does not affect the neutrality of certain EU countries and is consistent with the commitments of EU countries which are NATO members.

This provision is supplemented by the solidarity clause (Article  222 of the Treaty on the Functioning of the EU) which provides that EU countries are obliged to act jointly where an EU country is the victim of a terrorist attack or a natural or man-made disaster.

Source:  EUR Lex Glossary

« Back to Glossary Index
e-platform european union

The Member States of the European Union have decided to link together their know-how, resources and destinies. Together, they have built a zone of stability, democracy and sustainable development whilst maintaining cultural diversity, tolerance and individual freedoms. The European Union is committed to sharing its achievements and its values with countries and peoples beyond its borders.

This webiste was created and maintained with the financial support of the European Union. Its contents are the sole responsibility of the College of Europe in Natolin and do not necessarily reflect the views of the European Union

http://europa.eu https://eeas.europa.eu/delegations/ukraine_en

Unless otherwise indicated, this website and its contents are the property
of the College of Europe in Natolin.
All rights reserved.