Vijay Nambiar, a U.N. special adviser on Myanmar, briefed reporters following his visit to the country.
International leaders have called for an easing of sanctions against Myanmar in an effort to encourage stronger economic ties with the Asian country. General elections in 2010 moved the country toward democratic rule following years of military leadership.
Nambiar, however, relayed concerns expressed by U.N. Secretary-General Ban Ki-moon that ongoing fighting in Kachin and Rakhine states was undermining the country's political gains. While some matters were for warring parties to settle, the envoy said in a statement that simmering tensions "adversely affect the positive international atmosphere that had been generated so far."
The BBC reports Friday, meanwhile, that the government has announced it was ending its military offensive against Kachin rebels in the country.
The European Union's foreign policy chief Catherine Ashton announced Thursday the EU opening diplomatic offices in Yangon.
Ashton, in a statement, said the diplomatic gesture was in response to what she said where historic changes from Myanmar's government.