>> Kan's approval rating falls to 26% in June

It is the first time that Kan has made the conditions to his resignation clear, local media commentated.

Kan is under immense pressure from inside and outside of his ruling Democratic Party of Japan to step down as prime minister due to his perceived lack of leadership following the March 11 catastrophes.

Kan also opened up two Cabinet posts in the face of growing criticism about his handling of the March 11 twin disasters and ongoing nuclear crisis at the Fukushima No. 1 nuclear power plant.

Ryu Matsumoto, 60, was named reconstruction minister, Kan announced at a late Monday press conference.

Justice Minister Satsuki Eda, 70, will concurrently serve as environment minister, a post vacated by Matsumoto.

Goshi Hosono, 39, Kan's former special advisor, was named as state minister in charge of handling the ongoing crisis at the Fukushima nuclear plant.

Hosono has played a major role in liaising between the government and the plant's operator, Tokyo Electric Power Co., since the world's worst nuclear accident since Chernobyl was triggered by the March 11 earthquake and tsunami.

Kan said the reshuffle is to "prevent the reoccurance" of the incidents in Fukushima.

Shizuka Kamei, 74, leader of the DPJ's coalition People's New Party (PNP), has also been given a special advisory role to the prime minister, after having turned down the offer of becoming deputy prime minister.

Main opposition Liberal Democratic Party (LDP) lawmaker Kazuyuki Hamada has been sounded out as the next parliamentary secretary for internal affairs and communications in charge of reconstruction, after he expressed his desire to leave the LDP last week.

The utility firm whose reactors were crippled following the magnitude-9.0 quake and massive tsunami knocked out vital cooling systems at the plant's reactors, will be closely monitored by a new government task force who convened for their first meeting on June 27.

The task force will prioritize reconstruction and restoration efforts in Iwate, Miyagi and Fukushima prefectures -- the areas stricken by the March 11 disasters, which have left nearly 27,000 people dead or missing.