A coalition of opposition groups in Ivory Coast threatened on Monday to try to block presidential elections in October unless the government opens talks on issues such as insecurity and the electoral commission.

The National Coalition for Change (CNC), formed in May and led by former Prime Minister Charles Konan Banny, groups 13 political leaders, several of whom have declared themselves candidates in the Oct. 25 election.

With the economy booming in Ivory Coast, the world's largest cocoa exporter, President Alassane Ouattara is widely regarded as favorite. If no candidate wins a majority in the vote, a run-off will be held roughly two weeks later.

The CNC said it had not received replies to letters sent to Ouattara and his government expressing concerns about insecurity in parts of Ivory Coast that could hamper voting.

The coalition also said it had concerns about what it termed pro-government bias in both the voting register and the composition of the national electoral commission.

"Elections cannot and must not be held in Ivory Coast if we do not sit down and talk," said Jean-Jacques Bechio, CNC spokesman. "If our demands are not satisfied, there will be no election."

Bechio said the CNC would use all legal means to make itself heard, referring to street protests and sit-ins. He declined to comment on the possibility of an election boycott.

Ivory Coast was plunged into turmoil when then president Laurent Gbagbo refused to recognize Ouattara's victory in a 2010 election. More than 3,000 people were killed during a brief civil war before Ouattara was installed with the support of French and U.N. troops.

The security situation in francophone West Africa's largest economy has improved dramatically since then. Foreign investors are returning, drawn by growth forecast to reach nearly 8 percent this year, according to the International Monetary Fund, thanks in part to heavy public investment.

Some see the CNC's move as an effort by its members to win political prominence ahead of October's election, and possibly cabinet places after the vote.

Aichatou Mindaoudou, the U.N. special representative to Ivory Coast, appealed for restraint from all political parties and for a peaceful electoral environment.

"This election is a chance for the Ivorian people to finally turn the page on the crisis and reaffirm democratic principles," she said in a statement.