Commission President Ursula von der Leyen’s has been battling accusations of cronyism since awarding the highly paid job to Pieper, who like her hails from the same German political party. Pieper had been due to start the role Tuesday.

Over half of MEPs in the European Parliament voted in favor of an amendment last week telling von der Leyen to rerun the appointment process.

Pieper signed the contract on March 31, despite the fact that two other shortlisted candidates for the post, both women, had reportedly received higher scores on tests during the selection process.

The controversy around her envoy pick adds to a growing list of potential problems for von der Leyen as she seeks a second term as European Commission President.

European Commission Vice President Josep Borrell and Commissioners Nicolas Schmit, Paolo Gentiloni and Thierry Breton, who all work under com der Leyen, criticized Pieper’s appointment, in a sign that Commission unity is waning as the European election approaches.

Speaking to Handelsblatt, Pieper said: “Just as Breton boycotted my taking office in advance within the Commission, I currently see no possibility of fulfilling the legitimate expectations associated with the office.”