Prime Minister Yoshihide Suga said Monday dealing with COVID-19 is his "top priority," taking precedence over dissolving the House of Representatives for a general election.
The comment came a day after the ruling Liberal Democratic Party lost all three seats in parliamentary elections seen as a bellwether for a nationwide contest that must be held by this fall.
"I humbly accept the judgment of the people and after studying the results further will make necessary adjustments," Suga told reporters.
The elections, the first at the national level since Suga took office in September, were held amid dissatisfaction with the government's sluggish coronavirus vaccine rollout and a string of money scandals involving LDP lawmakers.
Opposition candidates on Sunday swept a re-held House of Councillors election in the Hiroshima constituency, an upper house by-election in the Nagano constituency and a House of Representatives by-election for the No. 2 single-seat district in Hokkaido.
The results showed that voters are exasperated with an "outdated and corrupt plutocracy," said Yukio Edano, leader of the main opposition Constitutional Democratic Party of Japan.
Edano pledged to step up cooperation with other opposition forces ahead of the general election, which must be held before the current four-year terms of House of Representatives members end on Oct. 21.
Suga has the power to dissolve the lower house before then, but political analysts say the LDP's defeat Sunday will likely encourage him to wait until after this summer's Tokyo Olympics.
Speaking at a party meeting, LDP policy chief Hakubun Shimomura called the results "extremely severe" and stressed the need to regain people's trust by bringing the coronavirus under control.
Questions about Suga's leadership may arise over the coming months, especially if his public support begins to fall again. The approval rating for his Cabinet stood at 44 percent in a Kyodo News poll conducted this month, up slightly from March but still far below the 66.4 percent seen immediately after its formation.
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