European Commission President Jean-Claude Juncker has cut short his summer holiday and returned to his home country of Luxembourg for an emergency gallbladder operation.
The European Union's executive said in a statement that Mr Juncker, 64, "will undergo an urgent cholecystectomy", referring to the surgical removal of the gallbladder.
Mr Juncker had been on holiday in Austria.
He is in the final months of his five-year term as European Commission president.
He had been scheduled to go to the G7 meeting in Biarritz, France, next week.
Mr Juncker has been troubled by a bad back over the past years.