Pope Francis continued his therapy and prescribed diet, which now includes eating solid foods, the Vatican said in an update on Sunday.

The Vatican said he did respiratory and motor physiotherapy and his condition "appears stable, with slight gradual improvements."

"However, the overall situation remains complex, prompting doctors to maintain a guarded prognosis," the Vatican also warned in its update.

Earlier on Sunday, the Vatican said the pope was responding well to treatment and had shown a "gradual, mild improvement" in recent days as he remains in the hospital recovering from double pneumonia.

POPE FRANCIS SHOWS 'SLIGHT IMPROVEMENT' DURING FOURTH WEEK IN HOSPITAL, VATICAN SAYS

The night was quiet; the Pope is resting," the Vatican said in its earlier statement.

Francis, 88, was admitted to Rome's Gemelli 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.

This is the fourth Sunday in a row that the pope will not appear for his weekly noon blessing, but the Vatican plans to distribute the message he would have delivered.

The pope's condition has remained stable, as he has had no fever and good oxygen levels in his blood for several days, doctors said. The doctors said that his stability "as a consequence testifies to a good response to therapy."

This marks the first time doctors have reported that Francis, who has chronic lung disease and had part of one lung removed when he was younger, was responding well to the prescribed therapies since he was admitted to the hospital more than three weeks ago.

Despite Francis' absence, the Vatican’s daily operations continued alongside celebrations of its Holy Year, the once-every-quarter-century Jubilee that brings pilgrims from around the world to Rome. The Holy Year is celebrating volunteers this weekend, and many are extending their pilgrimage to pray for Francis outside the hospital.

POPE FRANCIS CONTINUES TO REST IN HOSPITAL AS VATICAN'S HOLY YEAR PROCEEDS WITHOUT HIM

Canadian Cardinal Michael Czerny will preside over the Holy Year Mass on Sunday for the volunteers.

The pope has been using high flows of supplemental oxygen to help him breathe during the day and a noninvasive mechanical ventilation mask at night.

The Associated Press contributed to this report.