A Pakistani pupil has been expelled from his private school for getting married on the sly because teachers believe marital relations are inappropriate playground talk.

Ghairat Khan, a bearded seventh grader, is registered as 13 years old and attends classes at the English-language Peshawar Model School with 12 and 13-year-old boys, but insisted to AFP that he is 18.

It can be common for children to fall back several years at school in parts of Pakistan and Khan said he married his 16-year-old cousin because his father died and his mother was ill with asthma.

Under civil law in Pakistan, boys can marry at 18 and girls 16, but under Islamic law, younger unions are permitted with parental consent.

"After my father passed away, my uncle, he is the guardian of our family and he gave me the hand of his daughter and my cousin in marriage as my mother also wanted to see me wed in her lifetime," he told AFP.

About five feet six inches (170 centimeters), Khan said his family comes from the tribal district of Mohmand, which lies outside direct government control, but now lives in the northwestern city of Peshawar.

He says he got married on April 25 and asked the school permission for time off to attend a cousin's wedding. When teachers found out Khan was the groom, they expelled him, saying that getting married was against school rules.

"The school administration handed me a school leaving certificate saying they do not allow married students in their school. The certificate says the certificate was issued upon the request of parents," Khan said.

He has taken the school to court in Peshawar and a judge has summoned the school's principal and director on June 9.

"There is no law in Pakistan under which a school can expel students for marrying. Under Islamic law, minors can marry with consent of their parents," Khan's lawyer Isa Khan told AFP.

"On June 9, we hope the court will allow Ghairat to rejoin the school."

Principal Beatrice Jamil refused to discuss the case in detail because the matter was before the court.

"According to school rules, a married student cannot study in our school, because it affects other children, when they share their stories," she added.

The education minister in Khyber-Paktunkhwa province, Sardar Hussain Babak, confirmed there was no government bar on school pupils marrying.