By David Ingram

NEW YORK (Reuters) - New York Governor Andrew Cuomo said on Monday he would seek to ensure that women have access to late-term abortions in the state even if conservatives on the U.S. Supreme Court remove federal legal guarantees in place since the 1973 Roe v. Wade ruling.

Cuomo, a Democrat who is considered a potential candidate for his party's 2020 presidential nomination, proposed an amendment to the New York Constitution that he said would preserve the status quo regardless of future Supreme Court rulings.

President Donald Trump, the Republican who took office on Jan. 20, plans to announce a nominee to the Supreme Court on Tuesday. That person, if confirmed, is expected to restore the court's conservative majority after the death of Justice Antonin Scalia in 2016.

The high court ruled four decades ago that the U.S. Constitution protects the right of a woman to have an abortion until the point of viability.

The court defined that as when the fetus "has the capability of meaningful life outside the mother's womb," generally at about 24 weeks into pregnancy.

The court also recognized a right to abortion after viability if necessary to protect the woman's life or health.

If the Supreme Court were to overrule Roe v. Wade, as abortion opponents have long hoped, the procedure would remain legal only where state laws allow it.

In New York, a state law that dates to 1970 legalized abortion up to 24 weeks of pregnancy, and afterward only if the woman's life is at stake, with no exception for health. The law is not enforced but could be if Roe v. Wade were overruled, abortion advocates say.

The state's law was "revolutionary back in the day because it legalized abortion before Roe v. Wade, but is now unchanged," Donna Lieberman, executive director of the New York Civil Liberties Union, said in an interview this month. "The state law is not as protective as Roe," she said.

Dennis Poust, a spokesman for the New York State Catholic Conference, which opposes abortion, predicted that Cuomo's proposal would fail.

"How many abortions are enough?" he said in a statement, noting New York's high rate of abortions. "No one can credibly claim that access to abortion is under any threat in New York."

There were 29.6 abortions per 1,000 women in New York in 2014, compared to 14.6 abortions per 1,000 women nationally, according to the Guttmacher Institute, a nonprofit group that supports abortion rights.

Cuomo told a Planned Parenthood rally in Albany, New York, on Monday that women's rights were under attack in Washington.

"As they threaten this nation with a possible Supreme Court nominee who will reverse Roe v. Wade," Cuomo said, according to a transcript provided by his office. "We're going to protect Roe v. Wade in the State of New York."

New York State Attorney General Eric Schneiderman issued a legal opinion in September making clear that federal court rulings supersede the state's 1970 law.

For a constitutional amendment to succeed in New York, majorities in the legislature must approve it twice, in successive terms, and voters must approve it.

Republicans control the New York Senate, although it is possible some Republicans might support such an amendment if pressured by constituents who favor abortion rights, said Costas Panagopoulos, a political scientist at New York's Fordham University.

Opposition to Trump may galvanize liberals into being aggressive, Panagopoulos said.

"People are scared, and that might compel them to action in a way that different circumstances might have them sitting on the sidelines," he said.

For years, states have planned for a day when the Supreme Court might overrule Roe v. Wade. Some 19 states have laws that could restrict abortion in that event, while seven have laws that would still guarantee the right to an abortion, according to the Guttmacher Institute.

(Reporting by David Ingram; Additional reporting by Jonathan Allen; Editing by Frank McGurty and David Gregorio)