US punk rocker Patti Smith shook hands with Pope Francis at a general audience in St Peter's Square on Wednesday, saying afterwards she found the new pontiff "very interesting" and "liked him a lot".

Wearing a black beanie hat and an oversize brown coat, Smith and the pope appeared to exchange a few words in the square and the pope was seen laughing.

Smith, who is not a Catholic but followed the conclave in the news, said the pope had shown courage in naming himself after St Francis of Assisi.

The singer, who is in Rome for a series of concerts, said the saint represented humility, the renunciation of materialism and a love of nature.

Smith became a leading member of the New York punk rock movement following the release of her debut album "Horses" in 1975.

She is well known also for her social activism, as well as her work in the visual arts and poetry.

In an interview last year, pop star Madonna referred to her as a major inspiration.

The 66-year-old comes from a religious family but is not a church-goer. In one of her hits she sang: "Jesus died for somebody's sins, but not mine".