Portugal's president has vetoed a bill that would have allowed citizens as young as 16 to change their gender identity without needing a medical report as long as they had parental consent.

President Marcelo Rebelo sent the bill back to parliament, which passed the bill Apr. 13, asking that lawmakers include a mandatory medical report for minors wanting to change their gender on official documents.

In a letter sent to the head of parliament Wednesday, Rebelo said he understood the reasons for the proposed law but argued that "it seems reasonable for there to be a medical evaluation early on."

According to Portugal's constitution, lawmakers can either include the proposed change, or they need an absolute majority to pass it as it stands.