A new interior minister has been appointed in Burundi - removing a major obstacle to the peace process.
FDD leader Pierre Nkurunziza (l) and Domitien Ndayizeye (r) agreed to share government jobs out
Jean-Marie Ngendahayo, a Tutsi, was named by President Domitien Ndayizeye, who backed down after originally saying the post was reserved for a Hutu.
The Forces for the Defence of Democracy (FDD) say they will now return to the power-sharing government.
The FDD agreed to join the government to end a 12-year civil war between Hutu rebels and the Tutsi army in a 2003.
Mr Ngendahayo is a former communications and foreign minister, who has been in exile for 10 years.
The BBC's Prime Ndikumagenge in the Burundi capital, Bujumbura, says that mediator South African Deputy President Jacob Zuma played a key role in resolving the deadlock.
South Africa has played a key role in the peace process
Under the 2003 peace deal, 60% of cabinet posts are reserved for Hutus and 40% for Tutsis but the FDD argued that these percentages could be shifted slightly.
Our correspondent says that the rebels agreed to back down on their original nominee for the post, while Mr Ndayizeye also agreed to appoint former rebels to positions across the government and civil service, including state-owned companies and the intelligence services.
The distribution of such posts was covered in detail in the 2003 deal.
FDD spokesman Karenga Ramazani told the AP news agency: "Our ministers will attend the next cabinet meeting on Tuesday."
Meanwhile, FDD leader Pierre Nkurunziza has said he is unhappy with the way his fighters are being disarmed before being integrated into a new national army.
"We are against forced disarmament... as it has been set up," he said.
"Disarmament, especially after as deep a crisis as ours, isn't child's play, it is a process that requires tact."
Some 250,000 people have died during the civil war, which saw Hutu rebels fighting for a greater share of power from the Tutsi minority which has traditionally ruled the country.
Mr Ndayizeye's mandate was last month extended by regional leaders.
He will stay in office until 26 August, with elections to be held by 19 August.
The polls were supposed to take place in April, to end some 12 years of ethnic conflict.
Mr Ndayizeye is a Hutu but critics say he is a front for Tutsis who still wield the real power, through their domination of the military.