TOKYO - JAPAN'S internal affairs minister admitted on Saturday his supporters had misreported a 1 million yen (S$13,000) political donation, but said he would not resign.

Hiroya Masuda is just the latest in a string of members of Prime Minister Shinzo Abe's struggling cabinet to acknowledge mistakes in political fund reports.

'It is a serious mistake. I am deeply ashamed that it was not properly handled,' Mr Masuda told a news conference. 'I will take responsibility by explaining myself and I hope to continue to do my job,' Kyodo news agency quoted him as saying.

The funding report of Mr Masuda's political support group showed a donation of 1 million yen made on Feb 28, 2003, to his fund management organisation, but the organisation's report had no entry showing receipt of the donation, Kyodo said.

Mr Masuda said it had been mistakenly logged in a separate campaign fund report, the agency said.

Mr Masuda, a former governor of Iwate prefecture, was appointed minister of internal affairs and communications when Mr Abe reshuffled the cabinet on Aug 27. His brief includes overseeing political fund reporting by lawmakers, Kyodo said.

Mr Abe took office a year ago vowing to rewrite Japan's pacifist constitution, nurture patriotism in schools and keep economic reforms on track.

Now, after an election drubbing in July and the loss of five cabinet ministers to gaffes and scandals, he faces an uphill battle just to keep his job.

Leaders of opposition parties, which won control of the upper house in the July poll, have vowed to grill him over his appointees in a session of parliament that begins from Monday.

Mr Abe's latest setback comes after his new farm minister resigned on Monday over illegal dealings at a farmers' group he headed, just a week after the new cabinet was formed. -- REUTERS