A brazen art heist that gripped Canadians has been solved: a famed portrait of a scowling Winston Churchill stolen from an Ottawa hotel has been found in Italy and the thief has been nabbed, police said Wednesday.

The "Roaring Lion" portrait of the late British prime minister had been gifted to the Fairmont Chateau Laurier hotel in Ottawa by the late Armenian-born Canadian photographer Yousuf Karsh.

It was taken by Karsh after the wartime leader addressed the Canadian parliament in 1941, becoming a symbol of British defiance in World War II.

In August 2022, hotel staff noticed the photograph, hanging in a reading room next to the main lobby, had been replaced with a forgery.

Two years on, Ottawa police say they have, with the help of public tips and forensic sleuthing, found the culprit - a 43-year-old man living 370 kilometres west of Ottawa - and the stolen portrait in Genoa, Italy.

"The portrait was sold through an auction house in London to a buyer in Italy, both of whom were unaware that the piece was stolen," police said in a statement.

The suspect was arrested in April and charged with theft, forgery, and trafficking in stolen goods.

"We are thrilled about the iconic Roaring Lion portrait returning to its rightful home at the Fairmont Chateau Laurier," hotel general manager Genevieve Dumas told AFP.

"This portrait... is not only an irreplaceable work of art but also a significant piece of our hotel's history," she said.

The artwork is to be returned in the coming weeks to the hotel, which plans to once again put it on display for guests.

Karsh and his wife, after fleeing the Armenian genocide and settling in Canada, lived at the hotel for 18 years. He also had a studio there until 1992.

His other portrait subjects included Martin Luther King, Jr, Ernest Hemingway and Queen Elizabeth II.

According to historical accounts, Karsh plucked a cigar from Churchill's mouth just before taking his portrait, which made the British premier grimace.

The image is arguably the most iconic of Churchill and widely circulated, even appearing on the British five-pound note.

Maintenance staff had been the first to notice the portrait's disappearance.

As speculation swirled over the heist, former hotel guests shared their snaps of the portrait over the years, helping to narrow down the date when it likely went missing from December 25, 2021 to January 6, 2022.

The hotel, which had hosted Karsh's first exhibition in 1936, also confirmed with the photographer's estate that a signature on the print was a fake.