Lancaster House Treaties
Cameron and Sarkozy sign the Defence and Security Co-operation Treaty during the UK-France summit at London. | |
| Type | Defence treaties |
|---|---|
| Signed | 2 November 2010 |
| Location | Lancaster House, London, England |
| Signatories | |
| Parties | |
The Lancaster House Treaties (French: Traités de Londres, lit. 'Treaties of London') of 2010 are two treaties between the United Kingdom and France for defence and security cooperation. They were signed at 10 Downing Street on 2 November 2010 by British prime minister David Cameron and French President Nicolas Sarkozy. The two treaties collectively are sometimes referred to as the Lancaster House Agreement.
The two treaties were 'modernised' on 10 July 2025 on the occasion of their fifteeneth anniversary at the 37th Franco-British Summit, held in London, by President Emmanuel Macron and Prime Minister Keir Starmer. This was done to ensure the treaties matched both the changes in warfare and technology, as well as the European security situation following the 2022 Russian invasion of Ukraine.