The Senate unanimously approved Cardoso's nomination as central bank governor after he appeared before lawmakers to answer questions. Four new deputy governors were also confirmed.
Cardoso pledged to improve transparency, fix corporate governance, and restore diminished confidence in the autonomy and integrity of the central bank.
President Bola Tinubu had promised a thorough house cleaning of monetary policy at his inauguration in May after criticizing former Governor Godwin Emefiele's handling of the currency.
Cardoso said once the central bank has verified the extent of its obligations, it will need to find a way to settle them quickly.
"We need to promptly find a way to take care of that. It would be naive for us to expect that we'll be making too much progress if we're not able to handle that side of the foreign exchange market," he said.
Cardoso said he will maintain price stability, revert to evidence-based monetary policies and discontinue his predecessor's unorthodox monetary policies to bolster the country's naira currency.
Cardoso, who began work on Sept. 22 in an acting capacity, takes office following the resignation of Emefiele, who was suspended as central bank chief by Tinubu in June and later detained by security agents and charged with procurement fraud.
Cardoso's comments come at a time when the naira has slumped to a record low, reaching the psychologically sensitive 1,000 naira per dollar on the parallel market.
The official exchange rate was quoted at 785 to the dollar as of 1710 GMT.
Unmet forex demand on the official market due to inadequate liquidity and speculation in street trading added downward pressure to the currency, widening the gap with the official market where restrictions on trading were lifted in June.
By Elisha Bala-Gbogbo, Reuters
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