An Australian teenager, who was born female but lives as a male, has been given permission by a court to have both breasts surgically removed.

The 17-year-old, known as Alex in court and referred to as a boy, has a psychological condition that makes him unhappy with his gender.

The Family Court in Melbourne said the removal of both breasts would help Alex to build a new life as a boy.

The decision has angered Catholic groups, who view it as irresponsible.

Alex has "gender identity dysphoria", a psychological condition where a person believes they are the opposite sex, the Age newspaper reported.

Alex has been on hormone treatment since he was 13 to prevent menstruation, it said.

Social development

He applied to the court for a double mastectomy before he turned 18 - the age at which he would not need the court's consent and which he would no longer receive social support services as a minor.

Family Court chief justice Diana Bryant said Alex, who lives life as a male, was socially constrained by the breasts, avoided being hugged and wore binding at the beach.

"So it was quite an impediment to his social development, which everyone thought was very important," Judge Bryant was quoted as saying by the Age.

"Overwhelmingly, the evidence was that it was in his interests. And I made that order.

"I wanted to make it quickly so that he could have the operation straight away.''

Critics say that such radical surgery on a 17-year-old is irresponsible and premature.

Campaigners have said that a man from Melbourne who had a sex-change operation in his early 20s was now suing his doctors because he regretted the decision.