The European Central Bank (ECB) has discussed a 500-billion-euro ($593 billion) quantitative easing program, a source at the central bank told CNBC.
No decision has been taken, but the program would involve purchasing countries' investment-grade-rated sovereign debt—bonds with a rating of BBB-/Baa3 or higher.
Bloomberg first reported the news, following a global market rally on Thursday after ECB President Mario Draghi reiterated that the central bank was open to a sovereign bond-purchasing program.
Such a measure could potentially be announced at the ECB's next policy meeting on January 22.
Purchasing only investment-grade, rather than speculative-grade, debt would minimize the amount of risk the ECB or euro zone central banks take onto their balance sheets. It would exclude Greek and Cypriot sovereign bonds, both of which are "junk" grade.
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