Washington, Feb 8 (IANS): The US Supreme Court has blocked the implementation of a restrictive abortion law in the state of Louisiana in a 5-4 ruling.

In the 5-4 ruling issued late Thursday, Chief Justice John Roberts joined the court's liberal wing to stay the Unsafe Abortion Protection Act, which requires physicians to hold "active admitting privileges" at a hospital within 30 miles of the facility where abortion care is provided, the Hill newspaper reported.

Women's groups argue that the law has no medical justification and would restrict abortion. Abortion rights advocates welcomed the court's order, only hours before the law was to go into effect.

"The Supreme Court has stepped in under the wire to protect the rights of Louisiana women," Nancy Northup, the President of the Centre for Reproductive Rights, said in a statement cited by the New York Times.

Around 10,000 women seek abortions in Louisiana every year, and, according to them, if the law came into force it will allow only one physician to carry out abortions in the state legally.

President Donald Trump's two Supreme Court appointees, Justices Neil Gorsuch and Brett Kavanaugh, were among the four conservative members of the court who voted in favour of the law's implementation, according to Efe news.

Thursday's decision on abortion was the first one by the Supreme Court on the hot-button issue since the controversial confirmation of Supreme Court justice Brett Kavanaugh.

Kavanaugh had voted with the conservatives and filed a dissent where he said he would have allowed the law to come to force in the state to ascertain if it adversely affected women's access to abortion.

The Thursday ruling disappointed pro-life groups, who want the Supreme Court to reverse the abortion law, which was legalized in 1973.

The top court had ruled a similar Texas law to be unconstitutional in 2016. In the 2016 decision, five justices - one conservative - had declared it unconstitutional as it was found to offer no benefits to women's health while restricting women's right to seek abortion.

In the last few years, several conservative states have imposed restrictions on abortions, citing religious rights or women's health.