PHILADELPHIA — Progressive activists in Congress have put mounting pressure on President Joe Biden to direct the archivist of the United States to certify and publish the Equal Rights Amendment — which would become the first explicit mention of women in the U.

The ERA’s deadline expired decades ago, but the president argues that recent approvals by three states put the amendment over the top.

The remarks were largely a symbolic gesture of support for a century-long campaign to enshrine gender equality in the Constitution. But advocates said they could add heft to a future legal fight.