Yemen last year teetered on the brink of civil war, leading to the downfall of long-time President Ali Abdullah Saleh. Ban arrived in Sanaa to mark the first anniversary of a transition deal that brought about regime change in Yemen.
"Your country... was on the brink of civil war, even just one year ago," Ban said. "But you have overcome this with political courage and determination which meant, in the end, foresight and political wisdom have prevailed."
The Yemeni security situation is complicated by separatist ambitions and the presence of al-Qaida in the Arabian Peninsula, the Yemeni branch of al-Qaida.
The U.S. State Department issued a travel advisory warning U.S. citizens of the elevated security risk in the country because of terrorist activity there. U.S. citizens are advised to not travel to the country. Any citizens there are advised to leave.
Demonstrators in September attacked the U.S. Embassy in Sanaa. The threat level remains "extremely high," the State Department warned.