FRANKFURT (Reuters) - The European Central Bank has extended a deadline for filling three top jobs at its bank supervision arm after it failed to hire any women for the roles, two sources said, illustrating the bank’s long struggle to attract female talent for senior positions.

FILE PHOTO: The skyline with its financial district and the headquarters of the European Central Bank (ECB) are photographed in the early evening in Frankfurt, Germany, December 4, 2018. REUTERS/Kai Pfaffenbach

With only one woman on its 25-member Governing Council and just a handful of women on the Supervisory Board, the ECB has long been criticized by European lawmakers for fostering a culture that favors men, with males holding over three quarters of senior managerial positions.

Pressure on the bank only increased in recent months when the top two bank supervisors, Daniele Nouy and Sabine Lautenschlaeger, were replaced by men, seemingly countering the ECB’s stated goal of improving gender balance.

The ECB, which oversees 117 of the euro zone’s biggest banks with 21 trillion euros ($23.5 trillion) in assets, will now seek applications for the three internal Supervisory Board vacancies until June 12 instead of the original May 15 deadline.

An ECB spokesman declined to comment.

While the ECB is under no legal obligation to find women for the jobs, picking only men would put it in a politically untenable position and would likely hold up the approval of board member Yves Mersch to become the vice chair of the supervisory board, the sources said.

Mersch was picked by the ECB’s Governing Council in April to replace Lautenschlaeger as the second-in-command of bank supervision but he still requires the approval of EU lawmakers before he can take up the job.

The sources said that ideally there should be at least two women filling the six internal Supervisory Board seat to diffuse political tension over gender inequality.

A conflict over gender also risks slowing the Parliamentary approval of ECB board members, a potential headache as ECB President Mario Draghi and board member Benoit Coeure are both due to leave the bank in the coming months.

The appointment of Mersch to the ECB board in 2012 was held up for several months due to complaints by lawmakers about gender imbalance.

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