The currency initially lifted from Friday's close, then slipped into weaker territory.
A dealer traded the naira at a one-off rate of 194.10 to the dollar before the unit settled at 191.35 naira at 1118 GMT, close to a record intraday low of 191.97 it hit last week. The naira closed on Friday at a record low of 190.60.
The naira has been hitting record lows as dollar liquidity on the interbank forex market thins out amidst a collapse in the price of oil, Nigeria's main export.
Dealers said Total offered to sell $80 million to some lenders on Monday while Shell sold an undisclosed amount of dollars, to buy naira for their local operations. However, the market was awaiting the results from the sales.