A U.S. Senate defense budget bill for next year calls for setting aside US$7.5 million to strengthen the Air Force's seismic technologies program to better detect nuclear tests, congressional records showed Tuesday.

The National Defense Authorization Act for Fiscal Year 2017 authorizes the fund for the Air Force Research Laboratory's seismic technologies program, saying the program is a key component in efforts to identify and monitor nuclear activity.

"The committee notes with concern the continuing threat of nuclear proliferation as evidenced by North Korea's recent fourth nuclear weapons test," the Senate Armed Services Committee said in a report attached to the budget bill.

"The committee strongly supports the laboratory's efforts to continue to develop seismic technology needed to sustain and improve the capability of the United States to monitor nuclear tests," the report said. (Yonhap)