BERLIN, May 23 (Xinhua) -- Climate-friendly and sustainable cities would be key to achieving "ambitious climate protection," according to a statement published at the International Conference on Climate Action (ICCA2019) in Heidelberg on Thursday.

"Participants are sending a clear signal to the world" about the feasibility of ambitious climate protection and compliance with the Paris Agreement and United Nations (UN) 2030 Agenda for sustainable development, according to the statement.

Representatives from all levels of governments "committed to achieving sustainable and climate-resilient growth and development, delivering better quality of life for all," according to the declaration adopted in Heidelberg.

"Here in Heidelberg, it became quite clear that we can make it. We have gained new insights and partners as well as formed new alliances," said Svenja Schulze, the German Minister for the Environment.

"We have the knowledge and the will to act together and to support the implementation of the Paris Agreement," said Schulze.

ICCA2019 was jointly hosted by the German Ministry for the Environment, the state of Baden-Wuerttemberg and the city of Heidelberg.

During the opening ceremony of the conference on Wednesday, Winifred Kretschmann, Minister President of Baden-Wuerttemberg, stressed that climate change was "truly an issue of universal concern. Every month, every week, every day counts. We have no time to be pessimistic".

"A truly extraordinary mix of actors" had come together in Heidelberg to work on solutions that could feed into the international climate process, said Andreas Wolter, chairman of Climate Alliance and mayor of Cologne.

On Thursday, Heidelberg's mayor Eckart Wuerzner concluded that "cities and regions from all over the world have shown many examples of effective climate protection. But we cities want to achieve more. We need to switch to a fossil-free economy".

More than 1,000 participants from all over the world attended the two-day climate action conference in Heidelberg.