TOKYO, June 26 (Xinhua) -- The Cabinet of Japanese Prime Minister Shinzo Abe decided on Wednesday to hold the upper house election and vote-counting on July 21. Official campaigning will kick off on Thursday of next week.

The cabinet's approval of the upper house election schedule came on the last day of the current Diet session, in line with a law stipulating that votes must take place within 24 to 30 days of the end of the session.

A total of 124 seats will be up for grabs with 74 allocated to constituencies and 50 to proportional representation. Half of the seats in the upper chamber are contested every three years.

Last year, the Diet enacted legislation to reform the electoral system, which included the addition of six seats to the 242-seat house to reduce the disparity in the value of votes. Three seats will be added in next month's election and three more in 2022.

The new legislation also introduced a special quota for the proportional representation system that will allow some candidates to be elected according to their rank listed by each political party.

The ruling Liberal Democratic Party and junior coalition partner Komeito are aiming to win a majority of at least 63 of the contested seats. Opposition parties hope to end the LDP's dominance.

In recent months, speculation had grown that Abe might dissolve the more powerful lower house for a snap election to coincide with the upper house race. But he decided against a double election, senior administration officials have said.

During the regular session from Jan. 28, the Diet enacted legislation to expand child-care support by offering free preschool education. It also revised a law to ban parents and other guardians from physically punishing children following fatal cases of abuse committed in the name of discipline.