This is a completely new story with no relation to previous Gundam series. Set in the 21st century with Japan as the main stage where a mysterious army has invaded with super weapons called Mobile Suits, the protagonist stand against them with a mobile suit called "Gundam".
The year is 200X. A mysterious robot fell from the sky into Tokyo. The robot is called a "Mobile Suit". Meanwhile, another Mobile Suit named "Gundam" crash landed near Kurono.