The phrase "allied forces" refers to a group of countries or military units that have joined together to fight against a common enemy. They work together and support each other to achieve a shared goal. Full definition
But imagine piling on all of the other conventional forces, intelligence agencies and allied forces across the globe trying to work towards a single mission. (inc.com)
As Supreme Commander of Allied Forces in Europe, he used the highways to route traffic through France to supply Allied soldiers moving toward Germany. (transportation.gov)
The nail in the Christian coffin came with the invasion of Iraq by allied forces in 2003, when Saddam was ousted. (premierchristianity.com)