The ECB's chief economist Peter Praet, who is also a member of the ECB's executive board, said last week that falling commodity prices and a slowdown in China were hindering the central bank's goal of getting inflation back up to around 2 percent and pledged the bank would do more if necessary.  In the face of continued weakness and the heightened risk of deflationary shocks, there are three main options for additional policy support according to analysts. The ECB could cut interest rates again, increase the size of its monthly asset purchases, or extend the program beyond the current scheduled end date of September 2016, they said.  But further cuts to the deposit rate, which is already at -0.2 percent, would risk having negative consequences, including the prospective damage to banks' profitability, which could cause them to cut their own deposit rates or increase lending rates, moves that would likely hurt the growth of businesses in the euro zone.  Read MoreEuro zone unemployment hits 3-year low - but don't get out the flags yet  "Governing Council members have already indicated quite strongly that short-term policy rates have reached a floor. Accordingly, we expect hints of potential future policy support to centre on the Asset Purchase Programme," said McKeown at Capital Economics. She expects the ECB to extend its QE program beyond next year and probably increase the pace of purchases in the meantime.  Barclay's Gudin agreed. "We now expect further easing to be announced before year-end as we believe inflation is unlikely to return to levels consistent with the ECB's objective of price stability over the next two years," he added.
The euro could be in focus at Thursday's European Central Bank meeting, as currency strength threatens to undermine efforts to lift inflation.