Edmond Perret, a Swiss pastor and social advocate who led a Reformed churches umbrella group that in 1982 declared apartheid a sin and its theological justification heresy, has died at the age of 87.

Perret, who served as the general secretary of the World Alliance of Reformed Churches from 1970 to 1989, passed away on March 24 in Geneva, Switzerland, said the World Communion of Reformed Churches last week.

The WCRC was created in 2010 from the merger of the WARC and Reformed Ecumenical Council.

"The Reformed family of churches worldwide has lost a brilliant mind, a loving leader and a pastor committed to societal transformation," said WCRC general secretary Setri Nyomi.

In 1982, under his leadership, the WARC's highest governing body declared apartheid to be a sin. The General Council also approved a statement saying that theological justification of apartheid was heretical.

Perret, even in retirement, was a social advocate.

The WCRC noted that at its formation in 2010, Perret pointed to similarities between the global economic crisis and the story of Genesis where humankind seeks control over God's creation.

"The present global crisis," he said in a video message to the General Council, "is a wish for power, of which the power of money is not the least."

Perret was ordained in the Protestant Church of Geneva in 1950. Following theological studies at McGill University in Montreal, Canada, he served as a pastor in The United Church of Canada from 1951 to 1956.

He also served as President of the Synod of the Protestant Church of Geneva from 1964 to 1966.

Perret was mourned by his children, grandchildren and great-grandchildren as well as by his extended family, the WCRC said.