The Green Party says New Zealand must follow the lead of other countries, including Australia, and stop importing Japanese food.
The nuclear emergency at the earthquake and tsunami-damaged Fukushima nuclear plant on 11 March was this week given the same rating level as the Chernobyl disaster in 1986.
The Greens' food spokesperson, Sue Kedgley, says the Government must either ban food imports from Japan or test for radiation at the border.
Ms Kedgley says the United States, Singapore, Canada and India have also taken action.
The MP says radiation from the Fukushima plant is affecting the Japanese food supply and that will flow through to its imports.
She says New Zealand imports fish and crustaceans from Japan, which have the potential to be contaminated because much of the leaking radiation is going into the ocean.
Ms Kedgley says the Ministry of Agriculture and Forestry's claim it has confidence in Japan's food safety management is naive at best and foolhardy at worst.