The governor of the southern Japanese prefecture of Okinawa on Friday approved landfill work to relocate a controversial US military base within the prefecture, marking a breakthrough in negotiations after 17 years of friction between Tokyo and Washington on the base's transfer plan. Okinawa Gov. Hirokazu Nakaima announced the decision to agree to the landfill request by the Japanese government that will allow the construction of new military facilities in the prefecture's less-populated Henoko district in Nago City. Nakaima said he has notified the Defense Ministry's Okinawa bureau of his approval. The announcement paves the way for the Japanese and US governments to move the US Marine Corps Futenma Air Station from a densely-populated Ginowan City, also in Okinawa, to Henoko. Since 1996, the two countries have been working on the plan to move the Futenma Air base from a crowded residential area to the less densely populated area, both in Okinawa. But the Japanese government has been facing strong domestic opposition to the plan from local residents, as many islanders want the US base to be moved out of Okinawa entirely. The governor's approval comes after his meeting with Prime Minister Shinzo Abe on Wednesday, in which Abe promised to reduce the base-hosting burden on Okinawa and increase funding prefecture's economy until fiscal 2021. Japan, which has relied on the US to defend it for almost 70 years after its World War II defeat, hosts the largest concentration of US military in Asia. The island prefecture, which had been occupied by the US until 1972, has more than half of 50,000 troops in the nation. About 75 percent of all US military facilities in the country are also located in Okinawa, some 1,500 km south of Tokyo, Japan's poorest prefecture with a population of around 1.4 million. Many Okinawa residents have demanded the relocation of the bases in the wake of aircraft noise, accidents and crimes