GUE/NGL MEPs have voiced their concerns about the EU's future banking union architecture in a plenary debate on the issue.

GUE/NGL MEP Jürgen Klute said: "An internal market must go hand in hand with banking supervision rules but these must apply across the board, not just in eurozone countries."

He continued: "There is a concentration of power that is difficult to accept in the ECB. It is not acceptable that the ECB refuses any kind of democratic accountability, particularly on the banking supervision part of its work."

GUE/NGL MEP Marisa Matias said: "Granting supervisory functions to the ECB is wrong as it gives supervisory powers and monetary powers to the same body. Concentrating more power into the hands of the ECB is also wrong as it is an institution that has unparalleled statutory powers which go well beyond its remit. It is a super bank of super powers. The ECB remains an opaque institution with very little democratic control."

She added: "We continue to see serious conflicts of interests when it comes to financial regulation. It is as if we are at a football match and the referee is from one of the teams."