Benedict XVI pledges loyalty to his future replacement as he leaves Vatican for last time as Pope

The 85-year-old pontiff is currently being flown to the papal retreat at Castel Gandolfo, near Rome.

The pope had earlier promised "unconditional reverence and obedience" to his successor, as he bade farewell to cardinals at the Vatican this morning.

He also left with a plea for the College of Cardinals to unite and work together "like an orchestra" where "agreement and harmony" can be reached.

Shortly before 5pm local time the outgoing pontiff left the palace for the last time as pope and began the flight by helicopter to the papal retreat at Castel Gandolfo, south of Rome.

The pope yesterday made an outgoing address in front of 150,000 people in St Peter’s Square, Pope Benedict XVI

He said there had been times when “it seemed like the Lord was sleeping” during his crisis-hit papacy.

Benedict XVI said there had been moments of joy during his tenure, but that “stormy waters and headwinds” had left the church in difficulty.

He said that, despite the troubles, he felt God would not let the church “sink”, adding that while “the Lord gave us days of sun  and of light breeze, days in which the fishing was good’, there were also inevitable periods of “stormy waters and headwinds”.

Pope Benedict's resignation does not come into effect until 8pm this evening, at which point the doors of the palazzo will close and the Swiss Guards in attendance will go off duty - their service protecting the pope now finished.

In their plumed helmets and striped uniforms, the Swiss Guards are one of the most beloved traditions of the Vatican.

The bodyguards will stand at attention as the pope arrives by helicopter at his summer retreat.

When they walk off duty, it will be one of the few visible signs that Benedict XVI is no longer pope.