The artist has hung 22 orange rubber dinghies – the same kind thousands have used to cross the Mediterranean to reach Italy – onto the facades of Florence's historic Palazzo Strozzi in the centre of the Tuscan city.

The piece, called Reframe, draws attention to the plight of refugees as part of his retrospective, Libero (Free), which opens on September 23rd and will run until January 22nd.

“I have enormous respect for those people who fight for their freedom,” he said, adding that he considers refugees “heroes of our time”.

“Florence has historically been a free, non-conformist and fighting city,” said the city's mayor Dario Nardelli. “It's not an accident that Ai WeiWei has set his exhibition here.”

Lifeboats covering the Palazzo Strozzi.

Ai himself spent much of his childhood in exile, after his father was declared an enemy of the Chinese state.

Other parts of the exhibition, which is a retrospective of the artist's career, include a portrait of medieval poet Dante and four other Florentine dissidents, each made out of Lego, as well as photographs, video work and sculptures made between the '80's and today.

It is the first time an artist's exhibition has featured on the facade of the Palazzo Strozzi as well as inside the building, and Ai's works will also be on display in the city's Uffizi Art Gallery and the central market.