Central bankers' monthly bond purchases of 30 billion euros ($35 billion) and ultra-low interest rates are designed to stoke growth in the 19-nation single currency area and power inflation to their target of just below 2.0 percent.
Growth has picked up across the bloc, although at a slower pace in early 2018 than last year -- 0.4 percent between January and March compared with 0.7 percent in the previous three months.
Meanwhile, eurozone price growth surged to 1.9 percent in May, in line with the ECB's target.
"Core" inflation discounting the most volatile elements remains weak, but the data suggest that over 2.4 trillion euros of "quantitative easing" (QE) or mass bond-buying since 2015 has dispelled the risk of deflation, or a downward spiral of prices braking economic activity.
At their Thursday meeting in Latvian capital Riga, "the governing council will have to assess whether progress so far has been sufficient to warrant a gradual unwinding of our net purchases" of bonds, top ECB economist Peter Praet said last week.
Central bank President Mario Draghi has until now said governors did not even discuss a possible exit from QE at their gatherings.
That makes the topic's appearance on the agenda an important signal that the end is approaching.
"After Praet's remarkable speech, we expect a very exciting meeting on 14 June," ING Diba bank economist Carsten Brzeski said.