Myanmar's government called on the various ethnic groups fighting for more autonomy in the country to form political parties and disarm before moving any further with a national reconciliation agenda.
"It will be difficult for our ethnic groups to agree to disarm," the rebel leader told Thai newspaper The Irrawaddy. "For our group, we totally reject this draft."
He said there was still "heavy fighting" with the government forces under way in the mountains of the northern part of Shan state, where its estimated 1,500 fighters are based.
"We could not meet again with [mediators] to negotiate because there is more fighting in our area," he said.
Myanmar since 2012 has brokered peace agreements with more than a dozen armed ethnic groups in the country.
Myanmar earned international praise for the series of political reforms that began with general elections in 2010. National security challenges have overshadowed some of those reforms.