A group of 25 European banks have failed a key healthcheck of the region's financial system, exposing a 25 billion euro ($31.7 billion) shortfall on their books.
The European Central Bank also found that all of the euro zone's banks have not been strict enough in identifying toxic assets, finding an additional 136 billion euros in non-performing loans.
Of the 25 banks that have failed the ECB's test, which was a snapshot of their books at the end of last year, 12 of them have already covered their capital shortfall.
Those 13 banks still with gaps will now have two weeks to submit a plan to bolster their capital to the European Central Bank (ECB), which will decide whether or not it gets the green light. They will then have up to nine months to cover the capital gap. Any bank that fails to repair its books will then face the prospect of regulatory intervention.
"For banks that failed the test, the biggest challenge now is likely to be successful remedial action in potentially busy, volatile markets which may limit the windows for successful capital issuance," said Edward Chan, banking partner at Linklaters.
Of the 13 banks that still have to bridge the gaps in their capital, Italy faces the biggest struggle with nine of its banks on the blacklist. Monte dei Paschi dei Sienna had the largest capital hole to fill at 2.1 billion euros.
Other than Italy, banks in Greece, Cyprus, Belgium, Slovenia, France, Austria, Germany, Ireland and Portugal also need to raise money in the next two weeks.
The tests are a key test of whether Europe is serious about repairing its dysfunctional banking system. The ECB has come under fire over whether the tests have been rigorous enough and the "stresses" used were realistic.
This is not the first time Europe's banks have been stress-tested. However previous tests have been widely discredited as toothless when they passed several banks which then had to be rescued by governments as soon as the economic climate turned sour. It was the cost of propping up these banks that contributed to pushing countries like Spain close to collapse
ECB vice-president Vitor Constancio told CNBC Sunday that this time around the tests had a greater credibility.
"We had involved in the exercise almost 5,000 experts from private firms conducting the exercise on the field, " he said.
"So I think that this exercise can only be considered as a very credible one."
The ECB's tests have focused on the asset quality of 130 of the euro zone's key banks. Simultaneously, the European Banking Authority has tested 123 banks in the European Union – the 18-member euro zone and the 10 non-euro countries -- measuring how well lenders can weather differing degrees of economic downturn. The EBA tests are checked by the ECB in the case of euro zone banks, or the country's own central bank when it is outside the euro zone. In the U.K., the Bank of England will also conduct its own stress tests, with provision for bigger property losses – the results will be announced in December
Europe's economy is mired in slow growth and barely increasing prices The review is part of a broader effort to remove the uncertainty in the market that has hindered lending and weighed on the region's troubled economy.
The ECB's Constancio told CNBC that now the stress tests had been completed, and the bank had introduced such measures as cheap-rate long-term loans to banks to aid investment in business, the euro zone;'s banking industry would regain its confidence.
"So we hope that the new environment created by the conclusion of this exercise and our monetary policy will be more favourable for the banks to feel more comfortable to take their credit decisions, " he told CNBC.
The ECB vice-president added that now the stress test exercise had been completed, banks can start to see a change in fortunes, with their valuations on the financial markets improving.
"After the exercise, profitability will tend to increase, and the market valuations and the development of stock prices was already anticipating that. And it will continue," he said.
However, some industry-watchers are not so convinced, and are uncertain that the demand for credit is actually there.
"Even if banks do become more prepared to lend now that the stress tests are out of the way," said Howard Archer,chief UK and European economist at IHS Global Insight, "it is very far from certain that there will be increased demand for capital from the private sector in many countries given current euro zone weakness, faltering business confidence and the uncertain outlook amid geopolitical tensions."
"If the ECB's bank stress tests really do bolster confidence in the euro zone's banking sector, that is a very welcome and positive development. But this will by no means be sufficient in itself to turn around the euro zone's currently poor economic fortunes."
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