Francis is being treated at Rome's Gemelli hospital, where he was admitted on February 14 after struggling with breathing difficulties for several days.
Vatican spokesman Matteo Bruni said in a brief update on Friday that Francis had slept well overnight and was able to eat breakfast.
A Vatican official, who did not wish to be named because he was not authorised to speak about the pope's condition, said that Francis was breathing on his own, without help of any machines.
The pope was able to move around his hospital room, was taking some phone calls and was continuing to do some paperwork, the official said.
Their comments came after the Vatican said on Thursday evening that the pope's condition was "slightly improving" for the second day in a row.
The Vatican also said that Francis' hemodynamic parameters, a measure of the functioning of his body's circulatory system, were "stable".
RESIGNATION A 'DISTANT HYPOTHESIS'
Francis, who has been pope since 2013, has suffered bouts of ill health in the past two years. He is particularly prone to lung infections because as a young adult he developed pleurisy and had part of one lung removed.
One retired Catholic cardinal suggested on Thursday that Francis' fragile health could lead the pope to resign as leader of the 1.4 billion-member Catholic Church, as his late predecessor Pope Benedict XVI did.
But Francis has firmly ruled out resigning in the past, calling it in 2024 only a "distant hypothesis". Church law also requires that any papal resignation be "freely and properly manifested", meaning a pope's decision to step down cannot be influenced in any way by outside pressure.
Francis is known for keeping a brisk schedule, sometimes holding dozens of meetings a day. Vatican officials expect his latest health crisis may lead him to slow down the pace a bit.
The Vatican, which has said the pope will stay in hospital as long as necessary, is expected to give a further update on the pope's condition on Friday evening.
All the pope's public engagements have been cancelled through Sunday and he has no further official events on the Vatican's published calendar.
