Not officially, but as a result of the German invasion of France in 1939, and the implementation of the Vichy puppet regime, British, US and French forces did fight and kill each other, most notably the British sinking of the French navy at Mers-el-Kebir on 3 July 1940 and also French forces fighting British and US troops when they landed in Algeria (Operation Torch(initially called Operation Gymnast)) 8-16 November 1942 .
i wanty the answering
France and Britain had promised to declare war if Germany tried to obtain anymore territory. And they kept that promise when Poland was invaded.
italy
Germany after they invaded poland, austria, and france
Czechoslovakia
1939
If Hitler took Poland then Britain and France would declare war on him, which they did.
answered by: **El Tay**
Poland.
France declared war, after they had been invaded and taken over.
1987
By Nazi Germany invading Poland, and Britain's ally, France joining Britain in declaring war against Germany, which in turn led Japan to declare war against Britain and France, which then escalated the war from a pan European to Global (eventually).