The European Central Bank (ECB) Executive Board member Peter Praet said in an interview with the Spanish newspaper Expansión on Friday that there was a limit in lowering interest rates.

"It's clear that negative rates cannot be reduced indefinitely to ever lower levels," he said.

He added that the central bank would only cut its interest rate further if the inflation outlook worsened significantly.

"I don't think we're going to see these conditions materialising in the near future," Praet noted.

He also said that the banking union was needed, and the recent central bank's measures needed more time to show the effect.

Praet pointed out that the ECB did not discuss helicopter money.