A photograph of Winston Churchill snapped in 1941 has been found in Italy after going missing from an Ottawa hotel and replaced with a fake.

The photo - known as "The Roaring Lion" - was taken by Yousuf Karsh shortly after Churchill gave a wartime speech to Canada's parliament.

On Wednesday, Ottawa police said the portrait had been found in the possession of a private buyer in Genoa, Italy, who was unaware that it had been stolen.

Officials also announced the arrest of a man from Powassan, Ontario, in connection with the theft and illicit sale.

The 43-year-old man, whose name is covered by a publication ban, faces several charges in Canada, including forgery, theft, trafficking and property damage.

He was arrested on 25 April, investigators say and appeared in court in Ottawa the following day.

The photograph is one of the most iconic ever taken of Churchill, the British war-time prime minister, and shows him on Parliament Hill moments after Karsh famously took a cigar out of Churchill's mouth.

"I held out an ashtray, but he would not dispose of it...I waited; he continued to chomp vigorously at his cigar. I waited," Karsh later recalled. "Then I stepped toward him and, without premeditation, but ever respectfully, I said 'forgive me sir' and plucked the cigar from his mouth."

By the time Karsh returned to his camera, he wrote, Churchill looked "so belligerent he could have devoured me".

A staff member at the Château Laurier hotel first noticed the photograph had been replaced on 19 August, 2022.

"We are deeply saddened by this brazen act," the hotel's general manager said in a statement at the time.

Police believe the photo was stolen sometime between 25 December 2021 and 6 January 2022, amid strict Covid lockdowns.

Police say the photo - one of the most famous portraits ever made - was sold through an auction house in London to a private buyer in Italy.

"Both of whom were unaware that the piece was stolen," police said in their statement.

The suspect was identified by tips submitted by the public, forensic analysis and by using "open-source research", police say.

Later this month, Canadian investigators will travel to Rome to attend a ceremony in which the unidentified buyer will formally return the artwork.

"Once in Ottawa Police custody, the portrait will be ready for the last step of its journey home to the Fairmont Château Laurier, where it will once again be displayed as a notable historic portrait," police said.