A weekend statement from Ellen Johnson Sirleaf's office said exceptions to the restriction can only be granted by the president herself following a one-on-one meeting.
The West African nation's economy has been hit hard by the Ebola epidemic and price slumps for export commodities iron ore and rubber.
Business owners organised a three-day shutdown last week to protest the situation. Their grievances included the persistent fluctuation of the value of the Liberian Dollar.
The statement from Sirleaf's office deplored an "alarming situation of capital flight", though the president's critics say her own officials are responsible because they routinely send huge sums overseas.
--AP--
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