According to Iranian Agency, the UN's special envoy for Myanmar, Christine Schraner Burgener, will embark on a tour of Asian countries aimed at finding a solution to the country's crisis.
The tour will include stops in Thailand and China, but the exact details and timings for Burgener's trip have not been confirmed.
UN officials say Burgener wants to hold direct meetings with the generals in Myanmar, but the junta ruled it out.
"We have not permitted this. We also have no plan to allow it at this moment," Zaw Min Tun, a spokesman for the junta, told AFP on Friday.
Burgener confirmed that the military had shunned her.
"I regret that Tatmadaw answered me yesterday that they are not ready to receive me," she tweeted on Friday, using the local name for Myanmar's military.
"I am ready for dialogue. Violence never leads to peaceful sustainable solutions," she added.
Security forces in Myanmar have been using lethal force to quell weeks of unrest since the coup on February 1.
The Assistance Association for Political Prisoners says the crackdown on protests has left at least 614 civilians dead. According to the local monitoring group, nearly 3,000 people have also been arrested.