Japanese prime minister Shinzo Abe has announced he will dissolve the lower house of parliament and call a snap election for next month.
Mr Abe said at a news conference that he will dissolve the more powerful house in Japan's two-chamber parliament on Thursday when it convenes after a three-month summer recess.
The election is due to be held October 22.
Support ratings for Mr Abe's government have begun to rebound as attacks on its cronyism scandals have faded during parliament's recess, while opposition parties are regrouping.
Opposition MPs said there is no need to hold elections now.
Mr Abe said: "I expect opposition criticism is going to focus on (the scandals), and it's going to be a very difficult election."
Analysts believe his ruling Liberal Democratic Party will retain a majority, but could lose the two-thirds majority it holds with its coalition partner, the Komei party.
However, a big enough victory could help Mr Abe extend his hold on power. His three-year term as party leader ends next September, and he will have to fend off any challengers from within the LDP to remain prime minister.
Yu Uchiyama, a University of Tokyo politics professor, said: "For Mr Abe, now is the time. He is taking advantage of unprepared opposition parties as he seeks to prolong his leadership."
Support ratings for Mr Abe's government plunged to below 30% in July following repeated parliamentary questions about allegations that the PM helped his friend obtain approval for a veterinary college.
Recent media polls show the support ratings recovering to around 50%, helped by parliament's recess and a cabinet reshuffle in August which removed the defence minister and several other unpopular ministers.
This marks a significant turnaround from June, when the Liberal Democratic Party suffered a devastating loss in a Tokyo city assembly election to maverick Tokyo governor Yuriko Koike's new regional party.
Opposition MPs are scrambling to regroup.
Earlier on Monday, Ms Koike announced the launch of a new national party she will head, though she will remain as governor to focus on hosting the Tokyo 2020 Olympic Games and other issues.
She said her Hope Party will be conservative and push for transparency in government, women's advancement, the elimination of nuclear energy and other reforms.
Several parliamentarians, including defectors from the main opposition Democratic Party, have announced their intention to join her party.
Ms Koike said: "This is going to be a new force formed by members aiming to achieve reforms and conservativism.
"We are going to create a Japan where there is hope for everyone that tomorrow will certainly be better than today."
The Democrats, who held power in 2009-2012, have lost ground largely due to internal disagreements.