Erik Solheim, a former environment and international development minister in Norway, has taken over as executive director of the United Nations Environment Programme (UNEP).

He replaces Achim Steiner, a German and Brazilian national, who has been at the helm of the organization for 10 years.

Mr. Solheim assumes his new role as chief of the UN environment agency after three years as head of the Development Assistance Committee (DAC) of the Organization for Economic Cooperation and Development (OECD).

On taking up office, Solheim pledged to work with countries around the world to tackle some of the most pressing global environmental challenges, including ocean and air pollution, the destruction of ecosystems, climate change and the relationship between the environment and conflict and migration.

He also promised to focus on environment issues close to people, such as damage to human health from air pollution, UNEP said in a press release.

“There is an urgent need to fight climate change, halt ecosystem destruction, and reduce pollution for the benefit of all peoples everywhere. By protecting our planet, we protect ourselves and in the process can help bring every last person out of poverty. We all have a stake in a healthy planet,” said Mr. Solheim.