Why did joseph stalin insist that great britain and the united states begin a western front attack against germany in 1943

In order to alleviate the pressure of Nazi Germany in the eastern front during the Second World War. The need to open a new front can divide the German army to protect and reinforce all fronts and widen the opportunity to destroy the German forces during the war. USSR suffers mostly the attack during the war and the cry for the need of a new front from its western allies.