OTTAWA - The Bank of Canada is again warning about the Canadian dollar's persistent strength.

Deputy governor John Murray says the Canadian economic recovery may not be smooth, in part because the strong loonie is a barrier to growth.

Murray's caution is contained in notes of a speech delivered to a business conference in Berlin on Tuesday morning.

He says the global recovery is expected to be slow and protracted, citing high household and financial sector debt and trade impediments.

Still, Murray says Canada is enjoying several advantages over many other countries, including a sounder banking sector, low government debt and more balanced household spending.

The bank has been repeatedly warning about the dangers a strong dollar poses to Canada's industrial sector, but few economists expect governor Mark Carney to go beyond jawboning the loonie down.

The bank's official forecast for growth next year of three per cent is based on the loonie averaging about 86 cents US. It was trading modestly higher at near 92.50 cents on Tuesday morning.