Canadian Prime Minister Stephen Harper says his country is sending more soldiers than initially planned to a military exercise in Eastern Europe in response to Russia's recent actions in Ukraine.

Harper's announcement in Warsaw on Wednesday comes a day after President Barack Obama pledged to boost U.S. military deployments and exercises throughout Europe.

Harper's office said Canada plans to send a contingent of about 75 soldiers to Latvia this month to participate in Saber Strike 2014, a U.S.-led exercise. Those are in addition to 45 Canadians who were to take part in the exercise in Poland.

The Canadians are joining some 2,000 other troops from nine countries for the exercises. It takes place June 9-21 in Poland, Latvia, Estonia and Lithuania.