Transgender inmates jailed in Rio de Janeiro's penitentiaries will be able to choose incarceration in prisons for men or women, a first for Brazil.

The new rules were approved Friday by the state of Rio de Janeiro's department of prisons.

"It is treatment with dignity. It shows respect for this population," the head of the state prison system, Colonel Erir Ribeiro, was quoted as saying by the newspaper O Globo.

The new measures drew praise from gay rights advocacy organization Rio Without Homophobia.

"This is progress for LGBT rights in the prisons. Over the past 30 years, there have been innumerable recorded cases of discrimination," said Claudio Nascimento, the organization's director.

He told Globo that lesbians would remain in women's prisons "as a security measure to prevent their being victims of rape in units occupied by men," but transvestites and transsexuals will be allowed to choose whether to be interned in a facility for men or women.

He said transvestites and transsexuals who were housed in male prisons will now be allowed to wear prison outfits and undergarments for women and to wear their hair long.

The changes -- sought since 2001 by LGBT groups -- are expected to benefit 700 of the 43,000 prison inmates in the state of Rio.

"It's a victory for transsexuals, a population that becomes even more invisible to society in prison. With these pioneering measures in Rio, that is going to change," said Teresa Cosentino, the state's head of social assistance and human rights.