(CNN) The Central Bank of Nigeria has suddenly changed its policy toward money transfer operators, effectively blocking many services used by Nigerians to send money to and from the country. The decision to revoke the licenses of all but three money transfer companies was backed by a warning, issued on Tuesday, that advises Nigerians at home and abroad to "beware of the unwholesome activities of some unlicensed International Money Transfer Operators." Citing "the greater economic good of Nigeria," the Central Bank stated that it will "not condone any attempt aimed at undermining the country's foreign exchange regime." 'Draconian' rules The sudden move has created immediate backlash because it affects a large volume of money. Remittances to Nigeria totaled about $20.8 billion in 2015, according to data from Global Knowledge Partnership on Migration and Development.Nigeria halts operations of most money transfer companies operating thereThe move will affect about $20 billion in remittances
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