A senior figure in the Afghan Taliban says a brother and son of their late founder, the one-eyed Mullah Mohammad Omar, have been appointed to leadership positions in the insurgency.

Mullah Gul Rahman Saleem said on Tuesday that Mullah Mohammad Yaqoob, Mullah Omar's son, has been named to lead the Taliban military commission for 15 provinces.

Mullah Omar's brother, Mullah Abdul Manan, has been appointed head of religious affairs, Saleem, a member of the Taliban's ruling council, says.

The move consolidates the positions of both men as the new head of the Taliban, Mullah Akhtar Mansoor seeks loyalty from dissidents to shore up his own position.

Yaqoob and Manan had opposed Mansoor's ascension after it was revealed last summer that Mullah Omar had died more than two years earlier.