At its first monetary policy committee meeting of 2020 the bank raised reserves by 500 basis points, after majority of the members voted to increase the ratio to 27.5%. It kept benchmark interest rates on hold at 13.5%.
"Maintaining the monetary policy rate at its present level is essential for sustainable support to growth before any possible adjustment," Emefiele told reporters in Abuja.
Most analysts previously polled by Reuters had predicted the central bank would leave rates unchanged. Emefiele has said the bank would maintain its tight monetary stance in 2020.
"Today's announcement is, however, still a tightening of liquidity, and near-term, we would expect market interest rates to adjust to this," said Razia Khan, chief economist for Africa and the Middle East at Standard Chartered.
Nigeria, Africa's largest economy, emerged from its first recession in 25 years in 2017, but growth remains fragile. The central bank has tried to encourage banks to lend to stimulate the economy, which has swelled liquidity.
Inflation stood at 11.98% in December, rising for the fourth straight month, worsened by Nigeria's border closure in August to fight smuggling. The central bank said inflation was outside its band of 6% to 9% and that it wanted to curtail inflationary pressure.
Emefiele said the bank would continue to sustain the value of the naira, though its dollar reserve of $38 billion was shrinking, no adjustment was planned.
Last year, the central bank banned domestic funds from buying its treasury bills, keeping markets awash with naira. The move also contributed to lowering bond yields, keeping foreign investors away.
Foreign investors cut their participation in Nigerian government bond auctions last year because of lower yields. They moved into bills supported by the central bank.
By Paul Carsten and Camillus Eboh
