The ECB's interest rate decisions should not ignore the tightening effect on monetary policy of unwinding past asset purchase programmes, according to ECB Executive Board member Piero Cipollone. Speaking at an event organised by MNI, the Italian official said that while the policy rate remains the main tool for adjusting the ECB's stance, the role of quantitative tightening in influencing the financial and financing environment - through the yield curve or bank lending - should also be should be taken into account.