President Joe Biden said that US voters will have to defend the “fundamental” right to an abortion if the Supreme Court scraps constitutional guarantees allowing the procedure.

Biden cautioned that a leaked copy published by Politico of a draft majority opinion by the court ending the nationwide right had not been verified.

However, if the document proves to be authentic, abortion laws will depend on individual states and “it will fall on voters to elect” officials who back the right to the procedure in November’s midterm elections, Biden said in a statement.

Biden also called on Congress to enshrine legal abortion in US law, which would be the only way of overcoming the Supreme Court ruling that the leaked document apparently shows is set to be issued.

Biden said he would “work to pass and sign into law” such legislation but acknowledged the reality that the conditions are not right with today’s evenly divided Senate between his Democrats and Republicans.

“At the federal level, we will need more pro-choice senators and a pro-choice majority in the House to adopt legislation” that codifies the existing guarantees apparently set to be removed by the Supreme Court.

With many US states already enacting or preparing highly restrictive abortion laws, Biden said he had ordered advisors to study “a variety of possible outcomes in the cases pending before the Supreme Court. We will be ready when any ruling is issued.”

“I believe that a woman’s right to choose is fundamental,” Biden said, referring to the landmark 1973 Supreme Court case Roe v Wade that declared abortion a constitutionally protected right — and which is now apparently set to be overturned.

“Roe has been the law of the land for almost fifty years, and basic fairness and the stability of our law demand that it not be overturned,” Biden said.