World leaders had threatened sanctions after Togo's army named Faure Gnassingbe president hours after his father Gnassingbe Eyadema died on 5 February. The appointment violated the constitution, which was hastily amended.
Togo's neighbours in West Africa, a region anxious for stability after years of wars and uprisings, called the succession a coup and demanded elections as laid down in the original constitution.
The pledge to hold presidential elections was made after diplomats from the Economic Community of West African States (Ecowas) met Gnassingbe on Tuesday to press demands that the 39-year-old civilian reverse the succession.
"Ecowas wanted us to return to the old constitution and that is what we are going to do, and in 60 days elections will be organised in this country," said the official on Tuesday.
The official said he expected an announcement on Wednesday about elections.
The army justified Gnassingbe's appointment by saying it could not risk a power vacuum.
Eyadema, a former soldier and wrestling champion, seized power in a coup in 1976 and ruled for 38 years, becoming Africa's longest-serving leader.
Ecowas pushed Gnassingbe to
hold elections in Togo
Gnassingbe's appointment triggered riots in Togo's capital, Lome. Four demonstrators were killed in two days during clashes with police in an opposition stronghold.
Under the original constitution, the head of the national assembly, Fambare Ouattara Natchaba, was legally Eyadema's successor, pending polls in the former French colony.
It was not immediately clear whether Gnassingbe would stand down before the vote.
Earlier, Ecowas executive secretary Muhammad ibn Chambas had described the talks with Gnassingbe as fruitful but declined to give details, saying he had to first inform regional leaders.
The foreign ministers of Niger and Nigeria, the most vocal of Togo's critics over the leadership crisis, also took part in Tuesday's talks.
The crisis in Togo struck at the heart of African leaders' declared efforts to prove that the continent is able to govern itself and respect democratic principles.
Eyadema's authoritarian style was often condemned abroad, although he carved a role as a peacemaker on the African stage, most recently mediating in Ivory Coast's civil war. His son, who has a business degree from the United States, had held the influential position of minister of mines, equipment and transportation, post and telecommunications.