The U.N. Special Adviser for Myanmar, Vijay Nambiar met Tuesday with government leaders in the capital, Naypyitaw.
Thein Sein has declared a state of emergency and sent troops into Rakhine, where violence between ethnic Rakhine Buddhists and Rohingya Muslims has left at least a dozen people dead since Friday. Hundreds of homes have been destroyed by arson, U.N. officials said in a release.
Human rights activists say there is concern the military may be making arbitrary arrests. Chris Lewa of the Arakan Project in western Burma told Voice of America there are reports police are favoring the Rakhine over the minority Rohingya.
Nambiar said he and the president discussed the state of emergency and the need for the government "to continue to handle the situation transparently and with respect for human rights and the rule of law," U.N. spokesman Martin Nesirky told reporters in New York.
The Office of the U.N. High Commissioner for Refugees has called on Bangladesh to keep its borders open "to allow safe haven on its territory for those who need immediate safety and medical assistance," spokesman Adrian Edwards told a news conference in Geneva.
"Previously people have been allowed into Bangladesh for medical treatment. We hope that such good practices will be maintained," Edwards said.
More than 30,000 Rohingya refugees from Myanmar are living in two camps in the district of Cox's Bazaar in Bangladesh. There are an additional 200,000 "unregistered persons of concern" from Myanmar in Bangladesh, U.N. officials said.
U.N. Secretary-General Ban Ki-moon in April pledged continued support for Myanmar as it continues with the process of national reconciliation and democratic transition begun last year under Thein Sein.