Ivory Coast incumbent leader Laurent Gbagbo has ordered the seizure of all domestic branches of the Central Bank of West African States.
Gendarmes and armoured vehicles were reported to have surrounded the bank's headquarters in the city.
The bank has recognised Mr Gbagbo's rival Alassane Ouattara as president after disputed polls in November.
The bank's governor, an ally of Mr Gbagbo, was last week forced to resign by West African leaders.
The BBC says this effectively gave control of state accounts to Mr Ouattara, who ordered that two offices of the bank close.
Mr Ouattara condemned the move, which came amid an attempt by the African Union to negotiate an end to the crisis.
On Tuesday, the current chairman of the African Union, President Bingu wa Mutharika of Malawi, met the rivals in Abidjan.
Mr Ouattara was recognised by world leaders as the winner of an election on 28 November, but Mr Gbagbo refused to step aside after the Constitutional Council said he was the victor.