Matiullah Wesa has advocated for girls' education, particularly in conservative rural areas, for years.

This includes during the tenure of the previous Western-backed foreign government when he said many girls living in the countryside were not reached by education services.

Mr Wesa is the head of Pen Path, which has held meetings with tribal elders, encouraged communities and authorities to open schools, and disbursed books and mobile libraries.

He told Reuters last year his work was free of political interference and impartial and his focus was on helping communities encourage girls' education.

"Matiullah Wesa, head of [Pen Path] and advocate for girls' education, was arrested in Kabul Monday," the UN Mission to Afghanistan (UNAMA) said in a statement.

"UNAMA calls on the de facto authorities to clarify his whereabouts, the reasons for his arrest and to ensure his access to legal representation and contact with family."

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The Taliban administration in Afghanistan has barred most girls from high school and women from universities, saying there are perceived problems including around female Islamic dress.

Officials have said they are undertaking work to open schools but have not given a time frame.

They say they respect women's rights in accordance with their interpretation of Islamic law and Afghan custom and that the improved security in the country since foreign forces left has made it safer for young children to go to school.

The Taliban administration's information ministry and intelligence agency has not immediately responded to requests for comment or confirmed the detention.