Pope Francis has shown "slight" improvement over the past 24 hours, but remains in critical condition, the Vatican announced Wednesday.

Francis, 88, has been hospitalized in Rome for nearly two weeks as his prognosis remains undisclosed. He returned to his first work activities earlier this week, and Wednesday's update says he also carried out some of his duties.

"The clinical conditions of the Holy Father in the last 24 hours have shown a further, slight improvement. The mild renal failure found in recent days has returned. The chest CT scan, performed last night, showed a normal evolution of the pulmonary phlogistic picture. Today's blood chemistry and blood tests confirmed yesterday's improvement," the Vatican said in a statement.

"The Holy Father continues high-flow oxygen therapy; even today he has not presented respiratory crises. Respiratory physiotherapy continues. Despite registering a slight improvement, the prognosis remains confidential. During the morning, the Holy Father received the Eucharist. The afternoon was dedicated to work activities," the statement continued.

POPE FRANCIS SHARES WRITTEN MESSAGE WHILE CONTINUING HOSPITALIZATION

Francis was admitted to the hospital on Feb. 14 after a week-long bout of bronchitis worsened. Doctors first diagnosed the complex viral, bacterial and fungal respiratory tract infection and subsequently the onset of pneumonia in both lungs.

POPE FRANCIS HAD PEACEFUL NIGHT'S REST AT HOSPITAL FOLLOWING RESPIRATORY CRISIS, VATICAN SAYS

Late Sunday, doctors said blood tests revealed "early, slight kidney insufficiency" but that it remained under control. The doctors said Francis remained in critical condition but had not experienced any further respiratory crises since Saturday evening.

Francis, who had part of one lung removed when he was younger, was receiving high flows of supplemental oxygen, and received two blood transfusions on Sunday to increase hemoglobin levels. Doctors said his prognosis was guarded.

The pope was alert and responsive on Sunday and attended Mass.

Francis' condition is delicate, given his age, fragility and pre-existing lung disease, doctors said. The main threat to Francis, doctors warned, is sepsis, a serious infection of the blood that can arise as a complication of pneumonia.

Tuesday is Francis' 11th day in the hospital, exceeding the longest hospitalization of his papacy. He spent 10 days at Gemelli Hospital in 2021 after he had 13 inches of his colon removed.

Cardinal Timothy Dolan said Sunday in New York that the Catholic faithful were united "at the bedside of a dying father," an acknowledgment of Francis' short time left that church leaders in Rome have not said publicly.

Fox News' Landon Mion contributed to this report.