| Operation Wilfred–Plan R4 | ||||||
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| Part of the Norwegian campaign, Second World War | ||||||
 Map of Norway | ||||||
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| Belligerents | ||||||
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 Kriegsmarine | ||||
Operation Wilfred was a British naval operation during the Second World War that involved the mining of the channels between Norway and its offshore islands to prevent the transport of Swedish iron ore through neutral Norwegian waters. The Allies assumed that Wilfred would provoke German retaliation in Norway and prepared Plan R4 to occupy Narvik and other important locations. On 8 April 1940, the operation was partly carried out but was overtaken by events because of the German invasion of Norway and Denmark on 9 April (Operation Weserübung), which began the Norwegian Campaign.