The United Nations human rights office says Burundi's government has asked it to leave.
Spokesperson Ravina Shamdasani in Geneva confirms that they received a letter on Wednesday "requesting us to close the office. We of course regret this decision and we would like to continue our cooperation with Burundi."
She declined to comment further, calling the issue sensitive.
The East African nation's government has long been angered by UN reports describing alleged abuses amid the political turmoil since President Pierre Nkurunziza decided to run for another term in 2015.
Outgoing UN rights chief Zeid Ra'ad al-Hussein early this year said Burundi was among "some of the most prolific slaughterhouses of humans in recent times."