Explaining the letter, Flaherty accused Ontario's Liberal government of exercising "bad economic policy" by allowing corporate tax rates to remain the highest both in Canada and among the world's major economies.

"Ontario is discouraging investment," Flaherty told reporters. "That's bad for Ontario and it's bad for Canada."

In his letter, Flaherty takes numerous shots at McGuinty's leadership, accusing him of pointing "fingers at others for your problems" and reminding the premier "it's going to take political will" to mitigate the province's uncertain outlook.

Among the several bullet point suggestions for Ontario's upcoming budget, Flaherty lists: "You could focus on getting the economic fundamentals right."

The letter is the latest salvo in an increasingly bitter war of words between the province and the federal Conservative government. Source...