TOKYO - Japan is opening part of the evacuation zone around its leaking nuclear power plant for the first time since last year's disasters, allowing up to 16,000 evacuees to return home.

The 20-kilometre perimeter around the Fukushima Dai-ichi plant remains largely intact. But the government said Friday it would reclassify the least contaminated areas into three categories based on their radiation levels.

The towns of Kawauchi and Tamura will reopen starting Sunday, and Minamisoma in mid-April, affecting about 16,000 residents. However, most are waiting until the area is further decontaminated and infrastructure restored.

Parts of each town will remain off-limits because of higher exposure levels. Eight other municipalities in the same low-contamination category have not yet decided which areas should be reopened.

The nuclear crisis caused by the devastating tsunami on March 11, 2011, forced some 100,000 people to leave their homes because of radiation contamination. It is uncertain if those closest to the plant will ever be able to return.

Many who formerly lived in the no-go zone are divided between wanting to return home and fearing the contamination.