PHNOM PENH, Cambodia (AP) — Longtime Cambodian leader Hun Sen says will step down in three weeks as prime minister and hand the position to his oldest son.

The announcement Wednesday came after their Cambodian People’s Party won a landslide victory in weekend elections that Western countries and rights organizations criticized as neither free nor fair, and in which the country’s main opposition was suppressed.

Hun Sen has been Cambodia’s autocratic leader for 38 years but said ahead of the elections that he would hand off the position to his oldest son, Hun Manet, sometime during this next five-year term.

Hun Manet is currently the chief of the country’s army and won his first seat in Parliament in Sunday’s election.