Japan and the United States have agreed to speed up deployment of advanced Patriot interceptor missiles on US bases in Japan, officials said Monday, amid concerns that North Korea may test-fire a long-range ballistic missile. The two sides agreed earlier this month on the US plans to deploy Patriot Advanced Capability-3 missiles, designed to intercept ballistic missiles, cruise missiles or enemy aircraft, on its bases in Japan for the first time, a Defense Agency spokeswoman said on condition of anonymity. The US military would deploy three or four of the surface-to-air missiles on the southern island of Okinawa by the end of the year, where it also plans to send an additional 500-600 troops, Japan's largest newspaper Yomiuri Shimbun reported, quoting unidentified government officials. The plan was proposed by US officials during a June 17 meeting in Hawaii, the report said. The Defense Agency spokeswoman said the PAC-3 deployment sites have not been finalized.