ROME (AP) -- Pope Francis' overall clinical condition is "improving slightly" and his heart is working well as he battles pneumonia, the Vatican said Thursday, as some of his cardinals cheered him on and insisted that the Catholic Church was very much alive and well even in his absence.

In a late update, Vatican spokesman Matteo Bruni said Francis has no fever and that his key heart parameters "continue to be stable."

The 88-year-old pope was admitted to the hospital on Feb. 14 after a case of bronchitis worsened; doctors later diagnosed the onset of pneumonia in both lungs on top of asthmatic bronchitis and prescribed "absolute rest."

"If you really want him to rest, you have to hospitalize him," quipped Cardinal Jean-Marc Aveline, the archbishop of Marseille, France, referring to Francis' work ethic.

Aveline was speaking at a Vatican news conference about a Mediterranean youth peace initiative alongside his counterpart from Barcelona, Cardinal Juan Josè Omella. But given the limited amount of information about Francis' condition, they were peppered with questions about the pope's health and whether he might decide to resign if he doesn't recover fully.

"Everything is possible," Aveline said.

Regardless, Omella insisted that the life of the church continued even with Francis in the hospital.

"Popes change, we bishops change, priests in parishes change, communities change. But the train continues being on the move," Omella said.

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Another cardinal, Gianfranco Ravasi, had commented earlier in the day on the possibility of resignation when asked if Francis might decide to follow in the footsteps of Pope Benedict XVI and step down if he becomes too ill. Benedict became the first pope in 600 years to retire when he concluded in 2013 that he didn't have the physical strength to carry on the rigors of the globe-trotting papacy.

"There is no question that if he (Francis) was in a situation where his ability to have direct contact (with people) as he likes to do ... was compromised, then I think he might decide to resign," Ravasi was quoted as telling RTL 102.5 radio.

Francis has already confirmed that shortly after being elected pontiff he wrote a resignation letter in case medical problems impeded him from carrying out his duties. There is no provision in canon law for what to do if a pope becomes incapacitated.

There is no indication Francis is in anyway incapacitated. Bruni said he woke up Thursday, got out of bed and had breakfast in an armchair, and worked from his hospital room with his aides. Blood tests Wednesday showed a "slight improvement" in some inflammation indices for the 88-year-old pontiff, who had an acute case of pneumonia in 2023 and is prone to respiratory infections in winter.

Archbishop Giuseppe Satriano of Bari said he was sad that Francis was sick but confident he would recover, recalling he proved the naysayers wrong when he completed a gruelling four-nation trip to Asia in September.

"Even during the long trip in Asia, the Swiss Guards and gendarmes came back more tired than he, and we all feared he'd come back destroyed," Satriano said. "But he's a fighter, so I think he'll win this battle."

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