Japan's new environment minister admitted yesterday to mistakes in past political fund reports, dealing yet another blow to Prime Minister Shinzo Abe, who has been plagued by a slew of scandals in his Cabinet.

Both the farm minister and a junior minister resigned on Monday, just over a week after Abe reshuffled his Cabinet in a bid to revive his popularity following a crushing defeat for his ruling coalition in July's upper house election.

Four ministers have quit since Abe took office last September, mostly for irregularities in political fund reports, while another committed suicide.