Norihiko Akagi, whose predecessor committed suicide in May hours before he was to face legislative questioning over other financial scandals, apologized for administrative errors.

Asahi, a major Japanese daily, reported Friday that two political groups attached the same photocopied receipts to doubly book expenses worth about 200,000 yen (US$1,666; €1,220) for postage in 2003.

One of the two groups is a local branch, headed by Akagi, of the ruling Liberal Democratic Party in his constituency. The other is his own support group.

Akagi, returning from a trip to China to promote Japanese rice Friday evening, apologized.

"I am told it was simply paperwork mistakes," he was quoted as saying by Asahi. "I would like to apologize," he said. Other Japanese dailies carried similar reports.

Officials at Akagi's office were not available for comment Saturday.

Falsifying political fund reports can be punished by jail terms of up to five years or a maximum fine of 1 million yen (US$8,334; €6,105) under Japanese laws.

Akagi, 48, took office last month, replacing Toshikatsu Matsuoka.

But Akagi also came under fire soon after taking office over allegations by Japanese media and opposition leaders that he reported dubious office expenses over the past decade, prompting calls from the opposition bloc for Akagi's resignation, although Abe rejected such calls.

On Friday, Tadayoshi Ichida, secretary-general of Japan Communist Party, called for Akagi's resignation following the latest revelation. Ichida said, "We must also question sternly the responsibility of Prime Minister Abe who appointed him and keeps defending him," in a statement.

Japan's ruling and opposition parties wrapped up campaigning Saturday for one of the most hotly contested parliamentary elections in years. One-half of the seats in the 242-member upper house of parliament will be contested on Sunday.

Abe has alienated voters with his handling of the government's misplacement of millions of pension records, scandals and Matsuoka's suicide.