A Burundi opposition group that includes politicians in exile said on Tuesday it was ready to attend any new round of peace talks hosted by Tanzania, after a first round from which it was excluded.
The mediator, former Tanzanian President Benjamin Mkapa, said the first round was more of a "monologue" by the government but that he would meet with those who did not attend and might have "positive contributions" to make.
Burundi has been mired in a year-long crisis in which more than 450 people have been killed since President Pierre Nkurunziza pursued and won a third term. Opponents said his move violated the constitution and a deal that ended a civil war in 2005.
A new round of peace talks was launched in the Tanzanian city of Arusha at the weekend, after previous discussions in Burundi and Uganda over the past year collapsed or stalled.
But several opposition groups, including CNARED, an umbrella group that includes exiled politicians and former government officials, said the talks had little value as they and other leading opposition voices were left out.
"If President Mkapa decided to invite CNARED to the next round of talks, we will respond to his invitation," CNARED spokesman Pancrace Cimpaye told Reuters. Cimpaye had described the talks as a "monologue" when they opened on Saturday.
"Talks should be between Nkurunziza's side and all political parties and civil society grouping opposed to the third term."
The government has said CNARED is not a registered party.
In a closing statement on Tuesday, Mkapa said he would continue mediation efforts in the next two weeks, including speaking to those who had not attended the first round.
"I will continue and complete the consultations with those who did not come during this session, but whom I feel might have positive contributions to make to the process."
Arusha was also the location for negotiations that led to the deal to end the ethnically charged 1993-2005 civil war.
Renewed violence in Burundi has alarmed a region where memories of the Rwanda's 1994 genocide remain raw. Like Rwanda, Burundi has an ethnic Hutu majority and a Tutsi minority.
The violence in Burundi has so far largely followed political rather than ethnic loyalties. But diplomats fear ethnic wounds could reopen the longer strife continues.