At the Spring European Council in March 2007, EU leaders agreed that climate change and energy policies must be integrated to enable the EU to become the first high growth, low carbon global economy. This transition is essential to ensure economic, energy and climate security. The Treaty of Lisbon recognises climate change as an important strategic challenge and as a specific objective of EU policy. It provides a new legal base for the EU to act on energy security, liberalising energy markets and promoting energy efficiency and renewable energy, with the specific aim of preserving and improving the environment.