KYIV, Ukraine (AP) — There are many obstacles to a peace deal in Ukraine , but a diplomatic solution remains the only viable option, the newly appointed head of the U.N. refugee agency said Friday, warning that humanitarian operations are increasingly overstretched because of multiple global crises. Barham Salih, Iraq’s former president who was elected UNHCR high commissioner in December, made his first visit to Ukraine since taking office. After traveling to Ukraine’s front-line cities,