Japanese nuclear regulators said that robots have obtained the first radiation readings from inside the stricken Fukushima power plant's tsunami-damaged reactor buildings. The officials at Japan's nuclear safety agency said Monday that readings from inside the plant's number one and number three reactors show repair crews can go inside the buildings, but only for short periods of time. The finding improves the chances that the Tokyo Electric Power Company, which owns the plant, will meet its goal announced Sunday of safely shutting down all six reactors within six to nine months. In recent weeks, workers have focused on removing highly radioactive water from the basements and surrounding tunnels at the reactors before daring to venture inside. The two remote-controlled robots, provided by the United States, were sent into the buildings Sunday to measure the temperature, radiation and oxygen levels. TEPCO said the radiation levels remain high, but all the readings were within allowable limits for sending personnel into the buildings. The on-site inspections inside the buildings are the first since hydrogen explosions blew the roofs off two of the buildings shortly after the March 11 earthquake and tsunami. NHK Television said a robot was being sent into the number two reactor building on Monday. On Sunday, TEPCO officials presented their long-awaited roadmap for shutting down the reactors, which have been leaking radiation into the atmosphere and nearby ocean since their cooling systems were destroyed by the tsunami. The first step in the plan calls for reducing radiation leaks and removing radioactive water from in and around the reactor buildings over the next three months. TEPCO says it will take another three to six months to fully bring the radiation under control and achieve what is known as a cold shutdown of the reactors. The announcement brought little comfort to residents who have been evacuated from homes within 20 kilometers of the plant, many of whom remain housed in school gymnasiums. Public frustration with the slow pace of resolving the crisis was reflected in three opinion polls published Monday, which showed more than two-thirds of Japanese disapprove of the government's handling of the crisis. U.S. Secretary of State Hillary Clinton renewed pledges of support in the crisis during a visit to Tokyo Sunday. More than 20,000 U.S. troops have helped deliver relief supplies to tsunami victims along Japan's hard-hit northeast coast while nuclear power experts have traveled to Japan to offer advice.