The Constitutional Democratic Party of Japan, the nation's main opposition party, on Monday unveiled a set of pledges for this summer's Upper House election focused on improving the country's social welfare system to help people receive medical and nursing care without having to worry about their finances.

The party said it will aim to create a society in which elderly people can feel secure even if they do not have a large amount of savings.

The platform for the election, likely to be held July 21, was released as the government has faced strong public criticism over its estimate that, under the country's pension system, a retired couple will face a shortfall of ¥20 million if they live to be 95 years old.