Long dependent on domestic appetite, Japan's nuclear technology companies are increasingly looking to overseas markets, hopeful that foreign governments still trust in the reliability and safety of their technologies after the Fukushima nuclear accident.

Despite public criticism, Prime Minister Yoshihiko Noda has so far answered calls by conglomerates for support as they try to strike deals with countries including Vietnam, Jordan and Lithuania.

Last month, Noda met with Vietnamese Prime Minister Nguyen Tan Dung to reaffirm a $13 billion (¥1 trillion) deal in which Japanese companies will construct two plants for the energy-hungry nation. The government has offered low-interest loans to Hanoi over the purchase.