Uganda's President Yoweri Museveni (Photo: AP Photo/Rebecca Vassie)

JOHANNESBURG (AP) — South Africa's retired Archbishop Desmond Tutu on Sunday made an impassioned plea to Uganda's President Yoweri Museveni not to sign into law a harsh Anti-Homosexuality Bill that calls for a life sentence for some same-sex relations.

Tutu, a Nobel peace prize winner, said in a statement that Museveni a month ago had pledged not to allow the anti-gay legislation to become law in Uganda. But last week Museveni said he had reconsidered and would consult scientists on whether homosexuality is determined by genetics or by a person's choice.

Tutu said he is "disheartened" by Museveni's new position because there is "no scientific basis or genetic rationale for love ... There is no scientific justification for prejudice and discrimination, ever."

Tutu urged Museveni to strengthen Uganda's "culture of human rights and justice."

Uganda's controversial anti-gay bill was passed by the country's parliament in December. It must be signed by Museveni to become law.

Originally the bill called for the death penalty for some homosexual acts but the maximum penalty was changed to life imprisonment for repeat offenders. The penalty for first time offenders is 14 years in jail.

Homosexual acts are already illegal in Uganda according to a law that dates back to British colonial rule. The new legislation has much tougher penalties, such as jail sentences for conducting a same-sex marriage or failing to report to police someone who has gay sex.

Tutu said human beings are diverse and this requires tolerance, compassion and respect for one another.

Tutu called on Museveni to change course and instead concentrate on legislation against rape and sex with children. Tutu said that would provide more protection for children and families than criminalizing "acts of love between consenting adults."

In a statement released on Friday, Museveni said Uganda's scientists had reviewed studies and agreed that no single gene could be identified as a trigger for homosexuality. They suggested it is learned behavior that could be unlearned. Museveni said he asked the scientists if it was possible that a combination of genes could be responsible. If the scientists report back that they can find no genetic determination for homosexual behavior, Museveni said he would sign the bill into law.

Museveni said he is open to debate about homosexuality and he encouraged "the U.S. government to help us by working with our scientists to study whether, indeed, there are people who are born homosexual. When that is proved, we can review this legislation."

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