Mali
State Department official Christopher Landau said Tuesday he spoke on the phone with Mali's foreign minister to discuss security developments in the country.
The call comes in the wake of a U.S warning against travel to Mali.
Last week, Washington ordered non-essential embassy staff and citizens to leave Mali over security risks.
A blockade by Islamist insurgents has seen Mali's capital suffer widespread fuel shortages, prompting fears that the junta's control may be slipping.
The insurgents have attacked and set fire to fuel tankers on highways leading to Bamako in the last two months. Mali is landlocked and most of its fuel shipments come via Senegal.
Army soldiers have resorted to escorting convoys but the attacks have persisted.
Mali and its Sahel neighbors Niger and Burkina Faso have been embroiled in a deadly Islamist insurgency for over a decade.
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