Luxembourg Prime Minister Xavier Bettel has left the hospital after four days of tests and treatment for a persistent case of Covid-19 that forced him to delegate some of his work, the country’s government said.

The Luxembourg government said that “because of the improvement of his health,” Bettel will reclaim his full functions as prime minister on Friday. Finance Minister Pierre Gramegna had taken over some of the prime minister’s duties earlier in the week.

While hospitalised, Bettel, 48, was diagnosed with insufficient oxygen saturation. He also suffered from Covid-19 symptoms, including coughing, headaches and a fever, according to an AP report.