The top bureaucrat at Japan's finance minister quit Wednesday following allegations he sexually harassed female reporters, saying he wanted to clear his name.

Junichi Fukuda has denied a magazine report he harassed several women, but calls for him to step aside have grown in recent days.

Finance Minister Taro Aso announced the resignation late Wednesday, saying Fukuda told him he wanted to "clear his name."

"I thought it would be difficult to fulfil my job responsibility with the situation after the reports and offered my resignation to Finance Minister Aso," the top bureaucrat told reporters shortly afterwards.

"I apologise to the people I have caused trouble to."

The Shukan Shincho magazine last week reported that Fukuda had made inappropriate comments to several female journalists and on Friday released audio of what it said was the top bureaucrat at a bar with a reporter.

"I'll tie up your hands. Can I touch your breasts?" a male voice on the recording says.

"Shall we have an affair once the budget is approved?"

The magazine said several other women, who have not been identified, also accused Fukuda of inappropriate behaviour, including asking to kiss them and take them to a hotel.

Fukuda came out fighting earlier this week saying: "I did not have such a conversation with a female reporter."

"I don't recognise that I made sexually harassing remarks that would make female reporters feel offended," he added in a statement issued through the ministry.

On Monday, Fukuda he said he had no intention of resigning and added that he would sue the magazine for libel.

Aso initially appeared to dismiss the allegations against Fukuda, saying he had given the top bureaucrat a verbal warning and felt he was "sufficiently remorseful."

But he subsequently said Fukuda would be fired if the allegations were proven, and the finance ministry said Monday it had asked independent lawyers to investigate, urging any women who had experienced harassment to cooperate with the inquiry.

On Wednesday, Fukuda said he didn't "recall having such a horrible conversation."

"I don't know if the recorded voice was my own. But I'm aware that there are many who said it sounded like Fukuda's voice."

The Shukan Shincho has defended its reporting and on Wednesday said it had additional audio, purportedly of Fukuda sexually harassing a female journalist in 2016.

Japan has one of the world's worst records for female political representation and has deeply entrenched gender attitudes.

Just 2.8 percent of rape victims go to the police, according to a 2017 government survey, and the #MeToo movement that has raised awareness of sexual harassment worldwide has had a relatively muted reception in Japan.

The harassment scandal comes as Prime Minister Shinzo Abe's government struggles with the fallout from two cronyism scandals, one of which involves the alteration of official documents by finance ministry officials.