JOHANNESBURG -- Retired Anglican Archbishop Desmond Tutu, who earned a Nobel for his peaceful opposition to apartheid, is urging the Cape Town Opera troupe not to tour Israel until discrimination there ends.

In a statement Tuesday Tutu compared the troupe's visit next month to international artists performing in apartheid South Africa.

He says it would be "unconscionable" to perform "Porgy and Bess," which he says has a "universal message of nondiscrimination."

Tutu charges that by bringing international artists to perform, the Tel Aviv Opera House "advances Israel's fallacious claim to being a 'civilized democracy."'

Tutu has emerged as a sharp critic of Israel. Last month, he backed calls for a South African academic boycott of Israel.