Global leaders are honoring the late Wangari Maathai of Kenya, the first African woman to win the Nobel Peace Prize.
Maathai died at a Nairobi hospital on Sunday after a long battle with cancer. She was 71.
The Nobel Committee awarded Maathai the peace prize in 2004, citing her stand against Kenya's former oppressive government and her work to encourage women to improve their lives.
U.N. Secretary-General Ban Ki-moon said Monday that Maathai's death marks “a loss for Kenya and the world.”
U.S. President Barack Obama issued a statement saying Maathai's life and work are proof that “one person's simple idea,” starting small, can result in important changes. He said her legacy stands as an example “to persist in the pursuit of progress.”
U.S. Secretary of State Hillary Clinton said the world has lost “a powerful force for peace, democracy and women's rights.”
Maathai founded the Green Belt Movement in 1977 to help poor women in rural communities meet their basic needs for firewood, food and clean drinking water through a tree-planting program. The effort later grew to include focusing on issues of democracy, human rights, women's rights and peace.
The organization says it has mobilized hundreds of thousands of men and women to plant more than 47 million trees.
Maathai also served as a member of the Kenyan parliament, and as the country's deputy environment minister.
Maathai attended college in the United States during the civil rights era in the 1960s, and said that experience inspired her to return home and do something positive for the people of Kenya.
She was one of the founding members of the Nobel Women's Initiative, joining other female Peace Prize winners to support women's rights advocacy around the world.