Abortion could be made illegal in the US with Brett Kavanaugh on the Supreme Court, the Michigan attorney general has warned.

Concerns have been raised Roe v Wade – the landmark Supreme Court decision that legalised abortion nationwide in 1973 – could be overturned or radically undermined with new conservative justices Mr Kavanaugh and Neil Gorsuch sitting on the Supreme Court.

Dana Nessel, a Democrat who is the first openly LGBT+ person elected to statewide office in Michigan, told a crowd of abortion rights supporters it is “likely” Roe v Wade will be struck down by the high court’s conservative majority, but that she would not enforce such a ban in her state.

“I will never prosecute a woman, or her doctor, for making the difficult decision to terminate a pregnancy,” Ms Nessel said to applause at a Planned Parenthood Advocates of Michigan summit.

Michigan never formally repealed a 173-year-old law that bars women from getting an abortion. Having a pregnancy terminated could become a felony in the state, apart from when a woman’s life is in danger if Roe v Wade were to be overturned.

Northern Ireland abortion protest in Westminster Show all 7 1 /7 Northern Ireland abortion protest in Westminster Northern Ireland abortion protest in Westminster Derry Girls cast members Siobhan McSweeney and Nicola Coughlan (right) join MPS and women impacted by Northern Ireland's strict abortion laws PA Northern Ireland abortion protest in Westminster Heidi Allen (second right) joins the protest PA Northern Ireland abortion protest in Westminster A luggage tag on a suitcase, symbolising the women who travel from Northern Ireland to England for terminations PA Northern Ireland abortion protest in Westminster The campaigners march across Westminster Bridge PA Northern Ireland abortion protest in Westminster Counter-protesters Rebecca Morgan (left) and her daughter Helen, one, demonstrate in favour of Northern Ireland's current laws Getty Images Northern Ireland abortion protest in Westminster Protesters supporting Northern Ireland's abortion laws at Parliament Square Getty Images Northern Ireland abortion protest in Westminster Demonstrators pull suitcases to symbolise the women who travel from Northern Ireland to England for a termination AFP/Getty Images

“I think I can go four or maybe eight years without sending women to be butchered in back alleys,” Ms Nessel said, adding that citizens must elect candidates who support abortion rights.

She added: “If we can not and will not commit to make reproductive freedoms a priority in 2020 then we most certainly will lose them for the remainder of all of our lives and for those of future generations as well.”

The state Republican Party tweeted at Ms Nessel that her statements are “further evidence that you have decided to only uphold the laws that you agree with. We will accept your resignation at any time.”

Some 57 per cent of registered voters say Roe v Wade should remain intact, according to a Fox News poll from February.

The attorney general’s comments come in the context of Republican-led state legislatures moving to implement restrictive abortion bans across the US.

Abortion opponents in states across the US have been emboldened to attempt to provoke new legal battles that could lead Supreme Court justices to revisit the key case. But critics argue the Republicans are unnecessarily launching legal battles that will end up being both expensive and futile – with taxpayers potentially footing the bill.

Last week, Ohio became the seventh state to pass legislation that bans abortion after a heartbeat is detected and legislation is pending in 11 other states. None of the signed bills have successfully become law so far.

The “heartbeat bills” make it illegal for women to receive an abortion once a heartbeat has been detected in the foetus. This can be as early as six weeks into a pregnancy – a point at which many women do not yet know they are pregnant.

Rights organisations have accused the Trump administration of attacking women’s reproductive rights by reinstating the global gag rule, appointing anti-abortion rights activists to key posts in federal departments that handle women’s health and striving to cut Title X funding to health providers that carry out abortions or make abortion referrals.

Earlier this month, legislation was introduced in Alabama that would make carrying out an abortion at any stage of the pregnancy punishable by 10 to 99 years in jail – even in cases of rape and incest.