TOKYO - A senior lawmaker of Japan's ruling party says the prime minister could resign before August.

Katsuya Okada, the No 2 of the Democratic Party of Japan, told reporters Sunday that if Prime Minister Naoto Kan achieved three policy goals, he could step down before the end of August -- the last day of the parliamentary session.

Japanese Prime Minister Naoto Kan attends a cabinet meeting on environment and energy in Tokyo June 22, 2011. [Photo/Agencies]

Kan, criticized for his handling of the March tsunami disaster and a nuclear crisis at Japan's Fukushima Dai-ichi power plant, said on June 2 he was willing to resign. But he has not specified when.

Okada said Kan's three goals are the enactment of an extra budget for post-quake reconstruction, the passage of a bill to issue deficit-covering bonds and a vote on a renewable energy bill.