President Ndayizeye met FNL rebels two weeks ago

Burundian army chief Germain Niyoyankana said dozens of weapons were recovered from Forces for National Liberation (FNL) rebels in the clashes.

FNL spokesman Pasteur Habimana confirmed the losses in Nyabiraba province. The army lost one soldier.

Some 300,000 people have died in 10 years of war in Burundi.

The BBC's Prime Ndikumagenge in Bujumbura says the FNL rebels accuse the government army and the former rebels of the Forces for the Defence of Democracy (FDD) of working together to wipe them out.

Ceasefire

But Burundi's Defence Ministry has denied the claims.

"We don't mind when the FDD are fighting the FNL, but we are not together," an advisor at the ministry told the BBC.

The FNL have so far not signed up to the power-sharing deal that led the FDD rebels to join the government.

This is the first major fighting since an FNL delegation and Burundi's President Domitien Ndayizeye met two weeks ago for the first time.

Both parties agreed to end hostilities but the FNL has accused the government of not sticking to the agreement.

The rebels have now pegged the next round of talks with the government to the agreement to cease hostilities.

Our correspondent says the government has said it remains committed to the talks but would continue to counter rebel actions.