Madagascar President Andry Rajoelina arrived on a remote Seychelles island ahead of a meeting with the man he ousted in 2009, at crunch talks brokered by the regional bloc.
His rival Marc Ravalomanana arrived on Tuesday, a Seychelles government source told the AFP news agency.
Rajoelina and Ravalomanana were scheduled to meet later on Desroches Island for talks aimed at ending Madagascar's protracted political crisis.
And the 15-member Southern African Development Community (SADC), chaired by South Africa President Jacob Zuma, will bring the two men face-to-face on Wednesday.
"President Zuma in his capacity as chair of the SADC ... will be attending the meeting in Seychelles on Wednesday," said Mac Maharaj, spokesman for Zuma.
The rare meeting will come on the heels of what the army said was an "attempted mutiny".
The reasons for the mutiny are not yet clear. Defence Minister Andre Lucien Rakotoarimasy said on Sunday that the mutineers had not made any clear demands.
An opposition radio station, Free FM, however, broadcast remarks from a soldier declaring that the mutiny was a coup, announcing "the dissolution of the current state institutions and the installation of a military directorate".
The country's communications ministry on Monday accused the station of complicity in a plot against the government, warning that Free FM could face criminal charges.
The defence minister said three people, including the corporal who led the mutiny, were killed in a raid near the capital on Sunday.
Despite the unrest, Rajoelina flew to the Seychelles' main island of Mahe and was immediately transferred to Desroches, a private island 230km to the south where the talks will be held, a Seychelles official said.
Before leaving Madagascar, Rajoelina had confirmed earlier media reports that he would be meeting Ravalomanana.
"I will speak sincerely, and I am ready to resolve the crisis and to face the Seychelles meeting, even if there has been disruptive behaviour to create problems within the country," Rajoelina said.
"What we should know is that the divisions, disruptions and everything that is designed to overthrow the government, it's not the first time that this has happened," he said.
Al Jazeera's Haru Mutasa, reporting from Cape Town in nearby South Africa on Sunday, said that the meeting on Wednesday would be to "try to map out some way forward".
"But there are a lot of things that are still wrong in Madagascar, the political climate is still tense, and they are a long way off from any kind of concrete reconciliation," Mutasa said.
Rajoelina and Ravalomanana last year signed a "roadmap" toward elections, but the deal has yet to be fully implemented.
The Southern African Development Community regional bloc has imposed a July 31 deadline for the two rivals to settle their differences, so that a timetable for elections could be unveiled next week.
The Indian Ocean island of Madagascar has been mired in political crisis since Rajoelina ousted Ravalomanana three years ago, with the army's support.
Then-opposition leader Rajoelina led violent street protests against Ravalomanana and eventually seized power in March 2009 with the help of dissident army officers.
Rajoelina, a former disc jockey who was only 34 when he seized power, had to change the constitution to become eligible for the top job in future polls, has failed to garner broad international backing.
The army regularly intervenes in Madagascar's politics.
Ravalomanana has lived in self-imposed exile in South Africa since being ousted. But in 2010 he was sentenced, in absentia, to life in prison and hard labour for the murders of around 30 demonstrators, killed by his presidential guard in 2009 protests that led to his overthrow.
Terms of a possible amnesty have disrupted negotiations throughout the year, including establishing conditions for Ravalomanana's eventual return from his exile in South Africa - one of the conditions of the roadmap.
Ravalomanana was separately served with a summons last week over a $23m lawsuit filed by victims of the February 2009 unrest, and is expected to appear in a South African court on August 1.
He has twice tried to return to Madagascar, but officials there have both times prevented him and his wife from entering the country.