Japan's naphtha imports for the petrochemical sector fell 10% in March from the same month a year earlier, government figures showed on Wednesday, reflecting the impact of last month's devastating earthquake and tsunami.

Imports of naphtha for ethylene production amounted to 1,724,515 kiloliters (1,193,398 tons) last month, the Ministry of Economy, Trade and Industry said in a statement.

That compared with 1,925,164 kiloliters (1,330,333 tons) in the same month a year ago and 2,061,384 kl (1,429,212 tons) in February.

The March 11 earthquake disrupted production across the petrochemical sector.

Maruzen Petrochemical and JX Nippon Oil & Energy, an oil refining unit of JX Holdings, restarted their quake-shut naphtha crackers by early April.

But two crackers remained shut at the Kashima plant operated by Mitsubishi Chemical, with a total ethylene making capacity of 828,000 tons per year.

March imports cost $1,057,462,109, down from $1,255,357,146 in February, the data showed.