British and Soviet forces invade Iran, meeting little opposition, and their ambassadors in the capital Tehran demand that Iran accepts "protection" of oil supplies. This intervention also encourages Turkey to remain neutral. Soviet forces cross from USSR in the North, either side of the Caspian Sea, heading for Tehran. British land from the Persian Gulf at Bandar Shapur, Abadan and Khoramshahr, taking oil installations at Abadan. They sink 2 small Iranian warships and capture several Axis merchant ships. British troops advance from Baghdad in neighbouring Iraq, to seize installations at Kermanshah.
Operation Gauntlet. 527 Canadian troops supported by 118 Norwegian and British engineers capture the Norwegian island of Spitsbergen (600 miles south of the North Pole) to destroy coal mines before they are annexed and defended by the Germans. They land from troopship Empress of Australia, escorted by cruisers HMS Nigeria and HMS Aurora pus 3 destroyers (commanded by newly-promoted Rear Admiral Philip Vian). While 2000 Soviet miners are evacuated, the demolition teams remain on Spitsbergen to destroy coal mines and equipment plus 450,000 tons of coal and 275,000 gallons of fuel.
At 10.11, U-752 sinks Soviet minesweeping trawler T-898 in the Barents Sea, 80 miles East of Cape Chernyj (41 dead and 2 survivors). In the North Sea south-east of Iceland, British anti-submarine trawler HMS Vascama and a British Catalina aircraft of 209 Squadron sink U-452, 6 days into her first patrol, with depth charges (all 42 hands lost). Kriegsmarine orders 61 new submarines.
At midnight, 30 miles off Grimsby, East coast of England, British destroyer HMS Wolsey rams and sinks British minesweeper Kos XVI (Norwegian whaler taken over in July 1940 by Royal Navy but still with a Norwegian crew).