Canadian Prime Minister Mark Carney has introduced his first federal budget - a blueprint for how he plans to deliver on his promise to make Canada's economy the strongest in the G7. The ambitious plan, seen as a key test of the new leader and former central banker, is as much a political document as a spending blueprint. It warns that Canada is in an era of "significant change" not seen since the fall of the Berlin Wall, which is underscored by its rapidly shifting relationship with the US,