The government downgraded its basic assessment of economy, saying the March 11 magnitude-9 quake and tsunami, which left nearly 30,000 people dead or missing, have caused serious downward pressure on exports, production and consumption.
"Although the Japanese economy was picking up, it shows weakness recently, due to the influence of the Great East Japan Earthquake," the Cabinet Office said in its monthly report.
It was the first time in six months that the Japanese government had downgraded its assessment. Earlier on Monday, the International Monetary Fund (IMF) had cut its forecast for Japanese growth.
Japan's Economic and Fiscal Policy Minister Kaoru Yosano, however, said the negative impact of the disaster could be short-lived, Kyodo news agency reported.
His remarks came as workers of the Tokyo Electric Power Company (TEPCO) continued to remove highly radioactive water from the crisis-hit Fukushima Daiichi nuclear plant and cool a spent nuclear fuel pool.
A magnitude-5.8 quake also hit areas near the plant this morning, but it did not obstruct recovery efforts or cause any abnormalities, the government's Nuclear and Industrial Safety Agency said.
TEPCO, the plant's operator, kept pumping out highly polluted water from an underground tunnel-like trench to a nearby storage area inside the No.2 reactor's building.
The critical work began last evening and an estimated 200 tonnes of tainted water was moved to a "condenser". The utility aims to transfer a total of 700 tonnes of polluted water by tomorrow.
Hidehiko Nishiyama, a spokesman for the government's nuclear regulatory body, said that as a result of the operation, the levels of highly radioactive water that had been filling up the trench and the basement of the No.2 reactor's turbine building was lowered by 4 to 5 cm this morning.
Nishiyama also said TEPCO sprayed some 195 tonnes of fresh water into a spent nuclear fuel pool at the No.4 reactor's building, after finding out that the temperature of the water there was 90 C, much higher than the usual 20-30 C.
He said the radiation level in the air some 6 metres above the pool reached 84 millisieverts per hour before the water-spraying operation.
TEPCO is working to install seven steel sheets near a seawater intake for the No.2 reactor and set up "silt fence" curtain barriers near intakes for the Nos. 3-4 reactors at the six-unit plant to block the spread of radioactive substances in polluted water.
Japan yesterday raised the severity level of crisis at the crippled Fukushima plant to a maximum seven, bringing it on par with the 1986 Chernobyl disaster.
Nishiyama today said a seawater sample taken on Monday 15 km away from the city of Minamisoma, Fukushima Prefecture, showed a radioactive iodine-131 concentration of about 23 times the maximum level permitted under law, but added that it does not pose any health risks.
According to Japan's Science Ministry, small amounts of radioactive strontium have been detected in soil and plants outside the 30-km zone around the Fukushima plant where the government has advised people to stay indoors. Strontium tends to accumulate in bones could cause cancer.
The ministry has been monitoring the level of radioactive substances in soil and weeds in Fukushima Prefecture, national broadcaster NHK reported.
It found 3.3 to 32 becquerels of strontium 90 per kg of soil in samples taken from three locations in Namie Town and Iitate Village, 30 km from the plant.
An extremely small amount of strontium was also found in plants taken from Motomiya City, Ono Town and Otama and Nishigo Villages. The areas are 40 to 80 km from the Fukushima plant.
The ministry says the amount found is extremely low and will not have a negative health impact even if a person ingests one kg of the contaminated soil.
The samples were taken between March 16 and 19.
Japan's Sendai Airport, which was submerged by massive tsunami following last month's quake, partially resumed domestic flight operations today, with a Japan Airlines flight arriving from Tokyo's Haneda airport at 8 am local time.
The airport opening is expected to make it easier for volunteers and others from Tokyo and its vicinity, as well as western Japan, to visit the disaster-hit areas and accelerate relief activities there.
Meanwhile, more than 100 evacuation sites designated by local governments were swept away or inundated by the tsunami triggered by the March 11 quake just off the coast of northeastern Japan, according to Kyodo News.
Many people are thought to have lost their lives after fleeing to those sites believing they would be safe, but no data have so far been collected on the actual toll in those places.
According to the National Police Agency, the death of 13,333 people has so far been confirmed in last month''s twin disaster. Most of the deaths occurred in Miyagi, Iwate and Fukushima, the three hardest hit prefectures. Miyagi topped the list at 8,161, followed by Iwate at 3,838 and Fukushima at 1,271.
About 84 per cent, or 11,156, of the recovered bodies have been identified.
The agency also listed 15,150 people as unaccounted for, based on reports mostly from family members. Today, police announced for the first time that 776 are missing in Higashimatsushima in Miyagi.