A week after officially kicking off his White House bid, Wisconsin Gov. Scott Walker signed a new law that bans non-emergency abortions at or beyond 20 weeks of pregnancy on Monday.

Walker, a Republican presidential candidate, said the legislation outlaws abortions on expecting women who are on their so-called "late-term" unless the pregnancy poses a serious risk to the mother's life or health.

Receiving no support from Democrats, the 20-week abortion law makes Wisconsin the 15th state to have similar bans without any exception for pregnancies resulting from rape or incest.

"For people, regardless of where they might stand, when an unborn child can feel pain I think most people feel it's appropriate to protect that child," Walker said, according to Al Jazeera America.

Under the new state law, doctors in Wisconsin who perform an abortion at or after 20 weeks in non-emergency situations could be charged with a felony punishable by up to $10,000 in fines and three and a half years in prison.

Doctors would only be allowed to perform abortions beyond 20 weeks only if the mother is likely to die or suffer irreversible injuries within 24 hours.

The law's supporters say foetuses can feel pain after 20 weeks. As such, the law spares unborn children from experiencing an excruciatingly painful death.

But Wisconsin's new law is still open to legal challenge. In May, a federal appeals court struck down a 20-week abortion ban in Idaho for violating a Supreme Court precedent protecting abortions up to the point of viability or 24 weeks.

An Arizona ban was also struck down in 2013, and the Supreme Court declined to hear an appeal of that decision.

Walker's decision to sign the law could be seen as an effort to stand out in a crowded race of Republican presidential candidates using a core issue of abortion to get the nod from conservative Republicans.

The Republican governor has a long history of opposing abortions. He ran a TV ad that supported a bill that would leave abortion decisions between a woman and her doctor during his gubernatorial bid nine months ago.

But Sasha Bruce of leading abortion rights advocacy group NARAL Pro-Choice America accused Walker of lying to Wisconsin voters when he was elected governor after saying that abortion "is between a woman and her doctor."

"Now, in an effort to win the votes of the extreme base of the Republican Party, Walker has traded the health and well-being of women and families to score cheap political points," Bruce said.

The Democratic National Committee (DNC)'s Women's Media Director Kaylie Hanson also denounced Walker for signing the bill on Monday.

"This legislation is nothing more than a timely favour that will rally the GOP base just days after Scott Walker's presidential campaign kickoff. But the harsh reality is that this law will hurt women, as it puts up barriers to care for rape and incest survivors — no exceptions — and threatens the health of the mother," Hanson said, according to The Hill.