OTTAWA - Prime Minister Stephen Harper has warned Canadians that 2009 will be a difficult year, but in his annual Christmas message he also urged them to be optimistic.

"As we face the difficult year ahead, always remember that ours is perhaps the most peaceful and prosperous society on Earth," Harper said in a televised address to the nation.

The short message did not make specific mention of the economic crisis that has gripped the country since the fall. Nor did it get into the political meltdown that resulted in the suspension of Parliament earlier this month.

Instead, the prime minister focused on historic celebrations that took place this year, including the 400th anniversary of the founding of Quebec, British Columbia's 150th birthday and the 90th anniversary of the end of First World War.

"These historic milestones remind us of how fortunate we are to live in Canada," said Harper.

He also encouraged Canadians "to spare a thought and a prayer for the brave men and women serving Canada abroad," who are unable to be home this Christmas.

"Their courage and sacrifice is a credit to all of us," Harper said.

Liberal Leader Michael Ignatieff also had a Christmas message for Canadians, urging them to be "mindful of all those who are less fortunate than we are, across Canada and around the world."

"As we come together in celebration, let us also commit ourselves to a new year of kindness and compassion towards others," Ignatieff said in a message released Wednesday.