Nine Japanese political parties from the ruling and opposition camps agreed Thursday to oblige social media platform operators to work to lessen the negative impact of disinformation, misinformation and slander on their platforms in elections.

The parties, which include the ruling Liberal Democratic Party (LDP) and the opposition Centrist Reform Alliance, aim to enact legislation during the ongoing session of the Diet, Japan's parliament, ahead of unified local elections next spring. The agreement was made at a meeting of a cross-party council on election campaigns.

Actions expected to be taken by platforms include halting reward payments to users and improving the capacity to respond to content deletion requests.…