Myanmar earned praise for democratic reforms that began with general elections in 2010. Conflict between Buddhists and minority Muslims, however, has overshadowed recent political gains.
Ban, addressing delegates to a Friends of Myanmar meeting at the U.N. headquarters, said Wednesday the country has experienced "remarkable gains" since the group met in September.
"President Thein Sein has since renewed his commitment to peace, democracy and an open market economy," he said in a statement.
Myanmar's military this week released child soldiers but Ban said he was troubled by communal violence in the country.
The International Committee of the Red Cross said this week humanitarian operations were complicated in Myanmar because it is difficult to cross communal lines.
"There is a dangerous polarization taking place within Myanmar," the secretary-general said. "If it is not addressed urgently and firmly, underlying tensions could provoke more upheaval, undermining the reform process and triggering negative regional repercussions."
Ban said he received assurances the government is determined to resolve the issue.
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