The Catholic Church cannot be an authentic witness to unity in diversity if it only mirrors the divisions found in society, Cardinal Kurt Koch said Friday.

Koch told CNA June 5: "The Second Vatican Council in its constitution about the Church says that the Church is the sacrament of salvation, the sacrament of unity, and how we can demonstrate this beautiful sign of unity in the Church when we are divided?"

Catholics cannot help build Christian unity when "we are the mirror of the tensions and the divisions in the society," he noted. "And in this sense, it seems to me very important to refind the unity in plurality, in diversity. Because the diversity and plurality are not in opposition to unity."

According to the Swiss cardinal, "today we have many, many tensions, many conflicts, many problems, and this shows that to refind Christian unity is [even] more important."

He added that it was clear that Catholics "can be credible in the ecumenical situation only when we can refind unity in our own Church."

Koch spoke to CNA on the 60th anniversary of the creation of the Vatican's Pontifical Council for Promoting Christian Unity, which he has led since 2010.

The office for Christian unity was first established as a secretariat on June 5, 1960, by St. Pope John XXIII, a few years before Vatican II would emphasize the importance of ecumenism for the Church.

Cardinal Koch said: "How we can find unity in a plurality is a great challenge for the Church, and only when we can resolve this problem in Christianity can we help in the society to refind better unity in many, many diversities, and many, many splits."

He also spoke about the ongoing protests in the United States following the May 25 death of George Floyd in police custody, calling it "a very difficult situation."

He said he supported non-violent actions against racism because racism is a sin which violates the Christian teaching that every human being is made in God's image, regardless of skin color.

He said that Christians in the U.S had a duty to oppose "the very important sin" of racism.