Pope Francis thanked his personal nurse for encouraging him to greet the crowds in St Peter's Square on Easter Sunday, according to the Vatican, which said that these were amongst his last words.

The Argentine pontiff, 88, died on Monday morning from a stroke, less than a month after returning home from five weeks in hospital battling double pneumonia.

"Thank you for bringing me back to the square," Francis told his nurse, Massimiliano Strappetti, after what would be his final popemobile ride, according to the Vatican News, the Holy See's media outlet.

The pope appeared exhausted during Easter celebrations on Sunday, but nevertheless greeted the crowd and drove around St Peter's Square cheered by thousands of rapt worshippers.

"Do you think I can manage it?" he had asked Strappetti before taking the plunge.

The medic, in whom he had complete confidence, reassured him.

Francis then spent about 15 minutes waving at the crowd and blessing babies from his popemobile, flanked by numerous bodyguards.

The Pope spent the afternoon resting in his Vatican residence, Casa Santa Marta, and had a peaceful dinner, Vatican News reported.

On Monday, at around 5.30 am (0330 GMT), "the first signs of illness appeared," it said.

More than an hour later, he waved to Strappetti from his bed in what the media site described as "a gesture of farewell" before falling into a coma.

Francis was declared dead at 7:35 am.

"He did not suffer. It all happened quickly," Vatican News said, quoting people who were with the pontiff in his final moments.

"It was a discreet death, almost sudden, without long suffering or public alarm, for a pope who had always been very reserved about his health."

Francis credited Strappetti with once having saving his life for having persuaded him to undergo surgery for an inflammation in his intestine.

His funeral will be held on Saturday.