Prime Minister Stephen Harper, who is writing a book on the history of hockey, indulged his love of the sport Thursday by attending an NHL game in Calgary.

Harper, accompanied by his nine-year-old son Ben, watched as the Calgary Flames secured a playoff spot in the league's Northwest Division.

He said his book, which details "aspects of early professional hockey in the city of Toronto," has suffered since his Conservative party won the federal election in January.

Prime Minister Stephen Harper and his son, Ben, watch the Calgary Flames defeat the Colorado Avalanche on Thursday. (Jeff McIntosh/Canadian Press)
Prime Minister Stephen Harper and his son, Ben, watch the Calgary Flames defeat the Colorado Avalanche on Thursday. (Jeff McIntosh/Canadian Press)

"My original plan was to have that published by the end of this year, but I have to admit, that since Jan. 23, I've been spending a little less time on it than before, so we'll see," he said.

Harper said he's written about hockey for years now, using it as "an escape from the pressures of the job."

"I've had an interest in hockey history for some years, since I was a boy," he said.

The prime minister refused to predict which team might win the Stanley Cup, joking that hockey predictions could get him into more trouble than politics. However, Harper did say he likes the chances of both Calgary and the Ottawa Senators.