The United States has expressed “deep concern” about the political crisis in Mali, while urging rebels in the north to “cease military operations” that it says are compromising the country's territorial integrity.

In a statement Tuesday, State Department spokeswoman Victoria Nuland said Mali's political institutions will be further weakened if soldiers who launched a successful military coup last month do not immediately return power to civilians.

“Our call now is obviously not only for the civilian government to be restored, but for the Tuaregs to cease their violence, and once we get back to a civilian government, for that government and those with grievances in the north to engage in dialogue rather than to be trying to settle these issues by violence.”

Since launching a new rebellion in mid-January, Tuareg fighters have wrested control of Mali's major northern cities from the military. The rebels are fighting alongside an Islamist group, Ansar Dine, that is believed to have links to al-Qaida.

Malian soldiers complained they were not properly equipped to fight the rebels and carried out a coup in the capital, Bamako, on March 22, led by Captain Amadou Sanogo.

The United States imposed travel restrictions Tuesday on those who “block Mali's return to civilian rule.” The State Department said the restrictions support similar sanctions imposed by the African Union and the Economic Community of West African States.

The State Department also issued a travel warning advising U.S. citizens to avoid going to Mali, calling the situation there “fluid and unpredictable.”

Democratically elected President Amadou Toure is currently under the protection of his presidential guard at an undisclosed location near Bamako.