Which foreign country's phone calls are monitored by the NSA?

The NSA has built a system that is capable of monitoring 100% of one foreign country's phone calls. You don't think that country could be the Jooish state, do you?

The National Security Agency has built a surveillance system capable
of recording “100 percent” of a foreign country’s telephone calls,
enabling the agency to rewind and review conversations as long as a
month after they take