A young deaf boy took centre stage at a solemn papal audience yesterday – to his mother's horror and the pope's amusement.

During the address at the Pope Paul VI hall at the Vatican today the boy, who is mute, escaped from his mother's control and walked up the marble steps to the podium.

He walked towards a Swiss guardsman, took his hand and tugged at his lance before going down on one knee in front of him.

The boy's mother briefly spoke to the pope as she tried to pull the child away, saying that he was mute. Pope Francis told her to let him carry on playing.

'This child cannot speak. He is mute. But he can communicate,' the pope told hundreds of pilgrims. 'And he has something that got me thinking: he is free. Unruly ... but he is free,' he added to laughter. 'It made me think, "Am I so free before God?" 

'Let's ask the grace (of God) that he may speak.'

His small sister joined him on the podium.

The mother told the pope that the family came from his native Argentina. As she left the stage, a smiling Francis leaned towards Bishop Georg Ganswein sitting next to him and whispered: 'He is Argentinian. Undisciplined.'