Klaasen, who rose to fame in racially segregated South Africa, passed away on Sunday (15Jan17) after a battle with pancreatic cancer.

As a teenager Klaasen was disfigured in an acid attack, but went on to travel the world and perform with stars including Roberta Flack and Patti LaBelle.

South African President Jacob Zuma paid tribute to the musician, saying in a statement, "The country has lost one of its internationally acclaimed and respected jazz icons in Ms Thandi Klassen. Her passing is a tragic loss to the nation."

Klaasen was also an outspoken opponent of South Africa's apartheid laws, which made black and mixed-race people in the country second class citizens and enforced segregation.

Zuma praised her campaigning and actions in mentoring young South African musicians.

"We have lost one of the leading pioneers of South African jazz music and promoters of the country's cosmopolitan culture," the president said. "She was a role model to many of our young and upcoming musicians and her legacy will live on for generations to come."

Klaasen received one of South Africa's highest honours, the Order of the Baobab for "excellent achievement in and contribution to music" in 2006.