President Barack Obama’s pick to be the first American ambassador to Somalia in nearly 25 years has withdrawn her nomination, the White House told lawmakers on Monday, an unexpected suspension in U.S. plans to deepen ties with the African nation plagued by violence and instability.

An administration official said Katherine Simonds Dhanani, a career diplomat with experience serving across Africa, turned down the nomination for personal reasons and that Obama will have to find another candidate. The official spoke on a condition of anonymity without authorization to speak on the record.

The U.S. Embassy closed in 1991 when Somalia’s government collapsed in civil war, prompting the deployment of a U.S.-led U.N. peacekeeping mission. American troops withdrew from Somalia in 1994, months after the humiliating “Black Hawk Down” debacle when Somali militiamen shot down two U.S. helicopters. Eighteen U.S. soldiers were killed in the battle, which marked the beginning of the end of that U.S. military mission to bring stability.

Last week, John Kerry became the first secretary of state to visit Somalia. He cast the move toward restoring the ambassadorship as “recognition of the progress made and the promise to come.”

“I look forward, as does the president, to the day when both the United States and Somalia have full-fledged missions in each other’s capital city,” Kerry said in a video message to the Somali people in connection with his historic, albeit brief, stopover in the country.

Somalia has been without a truly functioning, nationwide government for two-and-a-half decades and has become infamous for its high rates of violence and the proliferation of pirates operating off its coasts. The current government continues to battle the al-Qaida affiliated al-Shabab militant group, which has staged attacks around east Africa and recently threatened shopping malls in the United States and other Western nations.

Security began improving earlier this decade as international efforts against al-Shabab gained ground, and the U.S. has been working to help Somalia move toward democracy and economic development. Still, al-Shabab continues to wage a deadly insurgency against Somalia’s government and remains a threat in Somalia and the East African region.

The State Department had planned to post Dhanani, who was awaiting Senate confirmation after being nominated in February, in neighboring Kenya until security conditions would permit the embassy in the Somali capital of Mogadishu to reopen.