The CA's Chris Hogg said fuel and power shortages are still acute in Japan.
Power cables have been restored at Japan's Fukushima Daiichi nuclear plant, which was seriously damaged in the 11 March earthquake and tsunami.
However, officials say further testing is needed before the electricity can be switched on. For now, seawater is being sprayed onto reactor No 3 to cool it. Work was interrupted earlier for the second time in 24 hours after steam and smoke was emitted from two reactors.Radiation levels spiked briefly, and engineers were told to leave the plant.
The work to restore power to the reactors restarted shortly after dawn. By evening, cables had been linked to all six reactors for the first time.
But the power supply will not be turned on until the equipment at the site has been checked first; only then will an attempt be made to restart the cooling systems and monitoring equipment.
Fire crews sprayed water on reactor No 3 for an hour to try to keep its fuel rods cool.
The rubble created by last week's explosions has been making it difficult for the trucks to get close enough to the reactors.
Workers have been battling to cool reactors and spent fuel ponds to avoid a large-scale release of radiation.
Higher than normal levels of radiation have been detected in seawater about 10 miles (16km) off the coast near the plant. Those levels appeared to be falling overnight though.
The plant's operator Tepco is investigating.
Power rationing
Police say the confirmed death toll from the earthquake and tsunami is now 9,079, with 12,645 missing.More than 350,000 people are still living in evacuation centres or temporary housing in northern and eastern Japan, many of them short of food, water and fuel.
The CA's Chris Hogg in Tokyo said major roads to the worst-affected areas were reopened to traffic on Tuesday, and bullet trains began running too.
That should make it easier to get relief supplies to the area and help address the shortage of fuel, our correspondent says.
Chief Cabinet Secretary Yukio Edano said a new government committee would meet regularly to co-ordinate with social agencies and ensure the evacuees were getting the support they need.
The government has also relaxed stockpiling rules on fuel wholesalers in a bid to get more fuel to the affected areas.
Power rationing has resumed across Japan because of shortages caused by the nuclear shutdown.
On Monday, the government ordered a halt to some food shipments from four prefectures around the Fukushima nuclear plant, as concern increases about radioactive traces in vegetables and water supplies.
Tepco will have to compensate farmers for losses caused by the nuclear radiation leaking from its power plants, the Japan authorities have said.
China, Taiwan and South Korea have announced plans to toughen checks of Japanese imports.
