Pope Francis used a wheelchair in public on Thursday for the first time since a flare-up of pain in his knee that has limited his ability to walk.

At an audience with a group of nuns in the Vatican's general audience hall, Francis was wheeled to his seat on the stage. An aide then helped him out of the wheelchair and onto his seat.

The 85-year-old pope has had to cancel or curtail activities several times over the past month because of the pain in his right knee.

Before Thursday, he had managed to walk the 10 metres (yards) or so from the side entrance of the stage to his seat at the centre, albeit with help from aides.

A Vatican source said the pope was not expected to make any changes to his schedule over the next few weeks - though the wheelchair would likely become a familiar sight as Francis tried to stay off his feet as much as possible to help his knee heal.

He is due to visit Lebanon in June, then South Sudan, the Democratic Republic of Congo and Canada in July.

Several times over the Easter period last month, Francis attended but did not preside at Masses in St. Peter's Basilica.

In each case, he delegated an archbishop or cardinal to say the Mass while he sat through the service and also read his homily while seated.

The pontiff said earlier this year that doctors would be giving him regular injections to help the movement of his joints. It is not clear if that therapy has begun.

He also suffers from sciatica, which causes pain in the leg and has left him with a limp.

The last time the pope was seen in a wheelchair was July last year in Rome's Gemelli hospital, where he had surgery to remove part of his intestine.

(Reuters)

Pope uses wheelchair in public for first time since knee pain flare-up