The Democratic People's Republic of Korea says a U.S. plan to build a new radar base in Japan would escalate a regional arms race, and leave Pyongyang no option but to develop "more powerful nuclear weapons."

The warning was made in a statement by the DPRK's foreign ministry, published by the country's Central News Agency. The ministry says the U.S. is building up arms against the DPRK, so the country has the right to bolster its own nuclear deterrent.

During a visit to Tokyo on Monday, U.S. Defense Secretary Leon Panetta said an agreement had been reached on deploying another US missile defense radar system in Japan.