Gay rights groups in Turkey expressed alarm Tuesday at a government-led project to build prisons only for criminals who declare themselves gay, saying it would lead to more discrimination in a largely homophobic country.

Justice Minister Bekir Bozdag announced at the weekend that plans were underway to construct separate prisons for openly gay inmates in a bid to "protect convicts" with different sexual orientations.

"Convicts who stated that they are gay will not mix with other convicts in the communal area or during social activities in the new prison facilities," Bozdag said in a written answer to a parliamentary question.

Unlike other Muslim countries, same-sex relationships are not criminalised in Turkey, a formally secular nation where prostitution and sex change operations are legal.

But traditional Islamic values hold sway over large sections of society in Turkey.

Gay rights groups voiced dismay last year that proposed legislation failed to make it a hate crime to target people because of their sexual orientation.

The situation is especially dire in existing prisons where, according to the justice ministry, homosexuals are effectively kept in solitary confinement.

"This is a medieval-age practice. This kind of segregation is nothing but a punishment" said Murat Koylu, a spokesman for the Ankara-based gay rights group Kaos GL.

"Instead of creating public areas where people from all sexual orientations can live together, the government has once again chosen to ostracise homosexuals," he said.

"This will lead to the profiling of gay prisoners, as well as their families and the prison itself. How will the government be able to protect those prisoners who are not openly gay?"

The ministry counts a total of 79 LGBT (lesbian, gay, bisexual, and transgender) prisoners in Turkey -- but the number is thought to be much higher since most homosexuals hide their sexual identities while imprisoned.

Although the ruling Islamist-rooted Justice and Development Party (AKP) has enacted a series of human rights reforms to boost Turkey's efforts to join the EU, it has not recognised homosexual rights.

Gay groups were among those joining nationwide demonstrations in June against Prime Minister Recep Tayyip Erdogan's government.