Friday's G-20 Summit events started with an unexpected announcement about a secret nuclear facility Iran's been hiding underground.

In response, U.S., Britain and France leaders warned the world would act soon if it discovers Iran is trying to build nuclear weapons.

CBN News Senior International Correspondent Gary Lane says U.S. Officials have known about the secret plant for years.

Click play for his explanation on why the whistle was blown on Iran now and what it could mean for foreign relations.