A Salvador Dali sculpture valued at $2.5-million has been vandalized while on display outside Quebec City's Château Frontenac.

Called Alice in Wonderland, the 4.5-metre-high bronze statue has been on display on the Dufferin terrace outside the hotel in Quebec City's old town for the past month to mark the 25th anniversary of the Château Frontenac's art gallery.

A staff that stands in front of the sculpture's central figure was broken off sometime overnight on Monday.

Sylvain Fortier, director of the Château Frontenac art gallery, said the bronze is very thick and there's no way this could have been an accident.

"I never would have believed that an immense bronze sculpture valued at $2.5 million and measuring 4.5 metres that's touring the world would be a target for vandals," he said.

Chateau Frontenac gallery director Sylvain Fortier said the bronze is too thick to have been accidentally broken off. (Radio-Canada)

Fortier said he's worried about the message it sends about Quebec City.

"It suggests we have no respect for the work of a great creator. It makes me very sad," he said.

The damage is repairable, he said, and the staff will be soldered back for now.

Prior to the incident, people had been climbing on the sculpture, which led to a barrier being erected around it.

Police are investigating.