CBN Governor tells Nigerians not to panic as bank shake-up looms
Diamond declined to comment, while UBA and GTB said they saw no need for a recapitalisation due to the devaluation.
For now, depositors and investors are generally giving the Central Bank of Nigeria Governor the benefit of the doubt after he shored up mid-tier lender Skye Bank this month with a loan and replaced its management when its capital fell below levels required by regulators.
But pressure is building, with loan books - nearly half of them in dollars - hammered by a shrinking economy, a plunging currency and acute foreign exchange shortages, all a consequence of the slump in the oil price for Africa's top crude producer.
Non-performing loans are expected to jump to 12.5 percent of total loans this year, up from the central bank's target level of 5 percent at the end of last year, as lenders suffer a hangover from an oil sector credit boom that ended abruptly in 2015, according to Agusto & Co, Nigeria's main rating agency.
Nigeria's 21 banks have been laying off staff, closing branches and slashing earnings forecasts, but some are unlikely to survive the storm, analysts say.
"It will affect their profitability, initially and eventually it is going to affect their liquidity and solvency," said Bismarck Rewane, chief executive of Lagos-based consultancy Financial Derivatives.
"Because of the squeeze in profitability there will be a natural consolidation and a shake out."
Any failure of the banking sector would have far-reaching consequences in the nation of 170 million, with civil servants' pay routed through the banks and residents of remote villages dependent on electronic systems for routine payments.
Sterling Bank chief executive Abubakar Suleiman said in February a naira drop of just 20 percent would trigger a "wave" of bank mergers. Since a devaluation last month, the currency has lost double that against the dollar.
Overall, 42 percent of loans extended by Nigerian banks are in dollars. If the naira falls far enough, it will force some banks to recapitalise to have enough naira to stay within financial stability limits.
"There is a concern around the evolution of banks' capital adequacy if the naira continues to weaken," said Standard Chartered Africa chief economist Razia Khan. "As the naira weakens, FX loans are likely to be problematic."
According to London-based analysts Exotix, UBA, Diamond and Guaranty Trust Bank (GTB), which is Nigeria's biggest bank by market capitalisation, have the highest ratio of dollar loans, at 50 percent apiece.
One Lagos-based banking analyst, who asked not to be named, said three or four medium-sized banks might need to raise capital. The central bank has said it is monitoring one or two lenders for liquidity, without naming them.
Adding to the uncertainty, GTB delayed its half-year earnings this week pending an interim audit.
Two mid-tier banks, Skye and Stanbic - the local arm of South Africa's Standard Bank - said they had not yet released first quarter earnings.
Some banks have themselves borrowed heavily in dollars, debt that now costs much more to service.
Top of this list is GTB, which has $1.6 billion in dollar-denominated debt, followed by First Bank of Nigeria, with $915 million, according to Thomson Reuters data. First Bank was not immediately available to comment.
Anticipating problems from a weaker naira, investors have been selling off banking stocks for the last year, sending the banking index in January to its lowest since it was formed in 2009, and less than half its level in mid-2014.
Many banking stocks - hot foreign investor picks a decade ago during an 'Africa rising' boom - remain depressed after a 2009 sector melt-down stemming from the global financial crisis.
Zenith shares are a third of their pre-financial crisis highs, Access a quarter, and First Bank just 10 percent. GTB, by contrast, has recovered as it has one of the lowest levels of non-performing loans and its shares are now in line with their 2008 levels.
With the IMF forecasting a 1.8 percent contraction in the economy this year, the immediate prospects for the banking sector are grim but Emefiele was adamant the financial system remained solid.
"The strategic health of the Nigerian banking or financial system remains strong at this time. There is no need for anybody to begin to panic or worry that any bank is in distress," he said after a monetary policy meeting this week.
"Depositors of banks, please, please endure. We appeal to you: go about your business. You will not lose your deposits in any bank."
However, his soothing words, which followed a rush by depositors to withdraw funds from Skye earlier this month, may have the opposite effect, especially after police in May raided three banks - Access, Fidelity and Sterling - as part of a probe into alleged illegal transactions.
"The moment you start saying it, it raises eyebrows - why are you saying that?" Financial Derivatives' Rewane said.
Another problem is the lack of transparency over so-called "insider loans" to directors and shareholders. These are often not declared in earnings statements in a timely manner, bankers say, making a bad picture possibly even worse.
The Nigeria Deposit Insurance Corp, an independent federal agency, said this week it was concerned "over the increasing wave of non-performing insider loans in various banks and its consequences for the stability of the nation's banking systems".
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