A row threatening to overshadow Ursula von der Leyen’s campaign for a second term as European Commission president has ended after a German colleague in her Christian Democratic Union party quit his new role as her special envoy for small businesses. Markus Pieper resigned from the €17,000-a-month (£14,500) role hours before he was due to start on Tuesday after pressure from MEPs and European commissioners who had raised allegations of favouritism. Opponents including the French commissioner Thierry Breton and the EU’s chief diplomat, Josep Borrell, had demanded that the appointments process be reviewed, claiming Pieper had not come first in the initial interviews process. Pieper said in a statement: “I successfully underwent a very demanding selection procedure. But the fact that commissioner Breton, of all people, who has been responsible for SMEs [small and medium-sized enterprises] and cutting red tape up to now, is now calling the procedure into question is bad form and motivated solely by party politics. “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. Things will look different after the European elections with the expected new majorities.” Allies of Breton dismissed allegations of a political power play. “Accusations of boycotting or party politics on the part of Commissioner Breton are ludicrous at best – not to speak of reverse engineering,” said one source close to the commissioner. Allies of von der Leyen have said that a letter opposing Pieper’s appointment penned by Breton and Borrell, along with Nicolas Schmit, the jobs and social rights commissioner, and Paolo Gentiloni, the commissioner for the economy, was entirely political. The allies said Pieper had come first in oral interviews that followed a written application and said Breton and the other commissioners had been given the opportunity before the appointment to raise objections but none were made. It is the second time in nine months that a top appointment in Brussels has been reversed. Last July, the US economist Fiona Scott Morton announced she would not be taking up a job in the commission after objections from Emmanuel Macron that the job should have gone to an EU candidate. “Piepergate”, as it has become known in Brussels, has been rumbling for two weeks, and has been seized upon as evidence that von der Leyen, previously considered a racing certainty for a second stint in one of the most influential jobs in Brussels, may yet falter. Member states are expected to back von der Leyen as candidate for the presidency after the elections in June but she will still need a majority of 361 MEPs in the European parliament. Five years ago she was elected with a margin of just nine votes. A spokesperson for the European Commission said: “The president both respects and regrets Markus Pieper’s decision not to take up his post as SME envoy.” They added that von der Leyen had decided to suspend the selection process until after the EU elections. Breton said he noted Pieper’s decision. “Transparency and collegiality are and should always remain our cardinal values. I hope that this important position for SMEs will be filled as soon as possible,” he wrote on X.