A women's rights group has stepped up its campaign demanding the government's top spokesman retract a remark last week in which he said that giving birth is a "form of contribution to the nation."

Since Oct. 1, the Project Japan Women's and Human Rights Network has been using the protest website Change.org to campaign for an official retraction from Chief Cabinet Secretary Yoshihide Suga.

The campaign has collected more than 10,000 signatures — about two-thirds of its goal of 15,000.

The gaffe came on Sept. 29, when Suga was commenting about two celebrities — singer and actor Masaharu Fukuyama and actress Kazue Fukiishi — who had announced their marriage the day before.

On TV, Suga said he wanted many woman to be inspired by the news and give birth to many babies "to contribute to the nation."

He later backed away from the statement.

"It's obvious that getting married and having children is a matter of personal freedom," Suga said. "To create a society that is supportive of child-rearing parents is a role of the government, and we are also working to realize a society where women can shine."

But Suga's excuse doesn't justify his gaffe, Kaori Sato, co-head of the activist group, said Thursday. The remark was problematic because it revealed that Suga, who at the time was in charge of gender equality issues, was still bound by gender roles, she said.

"What is missing completely from him is the attitude of recognizing one as a person, not by one's gender," she added.

The gender equality portfolio, meanwhile, was handed to new Cabinet minister Katsunobu Kato during Wednesday's Cabinet reshuffle.

The administration of Prime Minister Shinzo Abe has made the nation's shrinking birthrate a priority. At a news conference on Sept. 24, Abe pledged to push Japan's birthrate to 1.8 by 2020, from 1.42 in 2014.