Official campaigning began in Japan on Thursday for the July 20 House of Councillors election, a crucial test for Prime Minister Shigeru Ishiba and his minority government as voters struggle with the rising cost of living.

Ishiba has set a goal for the ruling coalition of his Liberal Democratic Party and the Komeito party to retain its majority in the 248-member upper house, meaning it will need to win at least 50 seats in the upcoming race in which 125 seats are up for grabs.

The target is seen as a relatively low hurdle for the ruling camp, which controlled the upper chamber before the election, although Ishiba, hit by low public support, has described it as not an easy undertaking.

The main opposition Constitutional Democratic Party of Japan is aiming to deal another blow to the ruling coalition by depriving it of majority control of the upper chamber. The LDP-Komeito camp lost its majority in the more powerful House of Representatives last October.

"We must ensure wage growth outpaces inflation, whatever it takes," Ishiba said during a stump speech in Kobe, western Japan, which this year marks the 30th anniversary of the magnitude-7.3 Great Hanshin Earthquake that killed more than 6,000 people in the region.

Ishiba, who has promoted disaster prevention measures, stressed the importance of distributing cash handouts, as pledged by the LDP, calling it a step to help households cope with higher prices. The LDP chief vowed to deliver them by the end of the year.

For the July 20 vote, over 520 people are expected to file their candidacies for the 125 seats -- 124 or half of the upper chamber and one to fill a vacancy in the other half.

Of the total, 74 will be chosen in electoral districts and the remaining 50 through proportional representation. In Japan, half of the upper house members are replaced every three years. Each member serves six years.

An emboldened opposition after the ruling coalition's defeat in the lower house election last year has made life harder for Ishiba, who has had to yield to opposition demands to ensure smooth parliamentary deliberations.

With Ishiba's premiership at stake depending on the election outcome, eyes are on whether the opposition camp can broaden its appeal, particularly the Constitutional Democratic Party of Japan and the Democratic Party for the People that surged in strength after the October general election. A conservative populist party, Sanseito, is also in focus.

"The government has not done anything effective," Yoshihiko Noda, the leader of the main opposition party, said in Miyazaki Prefecture, southwestern Japan, criticizing Ishiba's inaction on rising food prices.

Noda's party is promising to reduce the consumption tax on food from the current 8 percent to zero for one year. Miyazaki is home to the constituency of an LDP lawmaker who was forced to resign as farm minister after a gaffe about rice that was deemed insensitive to the struggles of consumers.

Pressure on household budgets is looming large, with both the ruling and opposition parties seeking to appease a frustrated public, though with different approaches.

The LDP and Komeito have pledged to distribute 20,000 yen handouts per person to help ease the pain of inflation. In contrast, opposition forces are pushing to cut, suspend, or even abolish the consumption tax.

With households hit by inflation, major political parties are promising to add impetus to the budding trend of wage hikes. Soaring rice prices have added to the recent bout of inflation driven by increased production costs, a headache for Ishiba.

The election will give voters an opportunity to deliver a verdict on Ishiba's months-old government at a time when Japan is seeking to stave off U.S. President Donald Trump's threat of even higher tariffs on Japanese products through rounds of bilateral negotiations that appear to have hit an impasse.

Ishiba, whose LDP has traditionally enjoyed support from agriculture groups, has vowed not to sacrifice the agriculture sector under U.S. pressure for more market access.