Rosary for pope's health takes place at earlier time as pontiff marks four weeks in hospital.

The nightly Rosary for the health of Pope Francis, who is battling double pneumonia in Rome's Gemelli Hospital for the past four weeks, will return to St Peter's Square on Friday evening.

The Rosary, which began in St Peter's Square on 24 February, was temporarily moved inside the Paul VI Hall earlier this week to coincide with the annual Lenten spiritual exercises for the Roman Curia.

The prayer service was originally held at 21.00 but now moves to 19.30, according to Vatican News.

The Rosary is open to anyone who wishes to participate and will be live-streamed on Vatican News media channels.

The health of Pope Francis, who on Thursday marked the 12th anniversary of his papacy, continues to improve however doctors warn that his clinical condition remains "complex".

Last week Pope Francis sent a surprise audio message, broadcast before the start of the Rosary, in which the 88-year-old pontiff thanked everyone for their prayers.

Photo credit: Marco Iacobucci Epp / Shutterstock.com.