European markets closed higher on Wednesday, as news emerged that the European Central Bank is set to buy around 50 billion euros ($ 58.3 billion) per month of government bonds for around a year. European stocks briefly spiked, before slipping to trade lower, after the Wall Street Journal cited sources in its report on the size of an ECB bond-buying program, which is widely expected to be announced Thursday.

The pan-European FTSEurofirst 300 (FTSE International: .FTEU3) provisionally ended around 0.5 percent higher after markets flipped between losses and gains for much of the afternoon session. The FrenchCAC (Euronext Paris: .FCHI) closed around 0.7 percent higher, Germany’s DAX (^GDAXI) ended up around 0.4 percent, while Italian stocks rallied to close 1.6 percent higher, led by banking stocks. The executive board’s proposal of at least 600 billion euro over the course of a year is above previous analyst forecasts of around 500 billion euro. Earlier on Wednesday, ECB Governing Council member Ewald Nowotny advised investors against building overly high expectations about the outcome of a single policy meeting — remarks that curbed enthusiasm about the likelihood of a large-scale bond-purchasing program earlier in the day.

Shares in Italy’s cooperative banks rose strongly on Wednesday after the government approved an emergency decree that forces the largest “popolari” to tighten their governance rules, which is likely to speed up consolidation in the space. Banco Popolare (Milan Stock Exchange: BP-IT), Popolare Milano and Popolare Emilia (Milan Stock Exchange: BPE-IT) were all up around 5 percent.

In the U.K., theFTSE (FTSE International: .FTSE)rallied to close 1.5 percent higher after the Bank of England voted unanimously to keep rates on hold this month for the first time since July last year. Two members of the bank’s Monetary Policy Committee that voted for a rate rise in previous months said a rate-rise now could dent the already below-target inflation rate.

In the oil markets , U.S. crude futures rebounded following steep losses a day earlier after comments from OPEC Secretary-General Abdullah al Badri, who expressed confidence that oil prices will bounce back. “Prices will rebound. I saw this 3-4 times in my life. We will go back to normal very soon,” he said, addressing the WEF in Davos.

Brent crude traded over $ 49 per barrel, while U.S. crude gained over 2 percent to trade over $ 47 per barrel. UK unemployment data was also released on Wednesday morning, showing that unemployment fell to 5.8 percent, it lowest level in over six year, and below Reuters forecast of 5.9 percent.

The FTSE (FTSE International: .FTSE) climbed 0.8 percent higher in afternoon trade, after thew news.The worst performer was Sports Direct (London Stock Exchange: SPD-GB), whose shares were trading down over 4 percent. On Tuesday, Goldman Sachs said it was selling up to 15.4 million shares in the sports retailer on behalf of founder and deputy executive Chairman Mike Ashley.

French group Alstom (Euronext Paris: ALO-FR) saw its shares rise 3.5 percent after the manufacturing company reported increased third-quarter sales and confirmed its full-year targets. U.S. stocks shifted to gains on Wednesday, extending a two-day run higher, as investors embraced reports that the European Central Bank would implement a large-scale bond-purchasing program.At the World Economic Forum in Davos, Switzerland, which kicks off Wednesday former Clinton Treasury Secretary Larry Summers told CNBC on Wednesday that breaking up the euro zone would be a “serious mistake” but the single currency has not lived up to the hype.

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Meanwhile, the Bank of Japan (BOJ) kept monetary policy unchanged on Wednesday, but cut its core consumer inflation projections issued three months ago, largely due to a collapse in global oil prices. The central bank’s governor Haruhiko Kuroda is due to hold a news conference in the afternoon to explain the policy decision. Elsewhere, U.S. President Barack Obama used his State of the Nation address on Tuesday to ask for a broad package of tax and other reforms in his annual address to lawmakers. He trumpeted the success of “middle-class economics” but also pushed for more reform. He called for unity from the Republican-led Congress to fight terrorism too.

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