Von der Leyen made the announcement on Tuesday as she presented the proposed new line-up of the European Commission, the EU's executive body, following the European elections held in June.
She said that Serafin, as the new European Commissioner for Budget, Anti-Fraud and Public Administration, would report directly to her, a move meant to raise his standing among the other commissioners.
According to her, Serafin will focus on preparing the EU's next long-term budget.
On the X platform on Tuesday, Polish Prime Minister Donald Tusk expressed satisfaction with Serafin's nomination.
"A strong portfolio for Polish Commissioner Piotr Serafin: budget, public administration and fighting fraud," Tusk wrote. "Or, to put it simply: Money, personnel and what we like most."
The proposed new European commissioners will now have to be approved by the European Parliament.
Serafin was a deputy foreign minister in the Donald Tusk government in 2010-2014 and the chief aide to Tusk when the latter was president of the European Council in 2014-2019. (PAP)
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