YANGON, Burma/Myanmar (AP) — Burma troops have clashed with ethnic Kachin rebels more than 20 times since signing an agreement last month to de-escalate fighting, a spokesman for the Kachin armed forces said Sunday, questioning the government’s commitment to the peace process.

“We cannot build trust just by holding talks,” La Nan of the Kachin Independence Army said in an email reply to The Associated Press. “It is necessary to have a firm commitment to resolve this through a political dialogue.”

There was no immediate response from the government.

Burma for decades has faced rebellions from several ethnic groups seeking autonomy. The KIA is the only major rebel group that has not reached a cease-fire agreement with the government of President Thein Sein, who came to power in 2011 after almost five decades of harsh military rule.

In their latest round of talks in May, the government and Kachin rebels signed a seven-point agreement to move toward a peace settlement.

But La Nan said there have been 21 clashes with government troops during this month alone.

He said the agreement to de-escalate fighting had given the government a chance to redeploy troops, send reinforcements and ammunition and get closer to KIA camps.

“It will be correct to say that the government used the opportunity of peace talks to prepare for the next assault,” La Nan said.

There have been 15 rounds of talks between the government and the KIA. No breakthrough is in sight, with the Kachin insisting on a political settlement, not just a cease-fire.