"The President of the European Commission Jean-Claude Juncker had to shorten his holiday in Austria for medical reasons. He was taken back to Luxembourg where he will undergo an urgent cholecystectomy (surgical removal of the gallbladder)", the report said.
Juncker's health has previously raised questions, as last year he was seen struggling to keep his balance due to a sciatica attack, as was later revealed by the commission.
It is also not immediately clear whether Juncker will be able to attend the G7 summit scheduled for next weekend in Biarritz, France.
Juncker has been in office since the end of 2014, his five-year term expires in late October this year. He will be succeeded by Ursula von der Leyen, deputy leader of the German Christian Democratic Union and former German Defence Minister.