The US Supreme Court on Friday blocked restrictions set by lower courts on a widely used abortion pill.

Justices at the top US court granted emergency requests from the Biden administration and New York-based Danco Laboratories, maker of the drug mifepristone. They were appealing a lower court ruling that would roll back approval from the Food and Drug Administration (FDA) for mifepristone.

The ruling is a win for President Joe Biden's administration as it defends broad access to the drug in the latest fierce legal battle over reproductive rights in the United States.

"The stakes could not be higher for women across America. I will continue to fight politically-driven attacks on women's health," Biden said in a statement after the ruling. "But let's be clear — the American people must continue to use their vote as their voice, and elect a Congress who will pass a law restoring the protections of Roe v. Wade."

What was the case about?

The case stems from a ruling by a US District Court judge in Texas, in a lawsuit brought by anti-abortion groups, that would have banned mifepristone,

The Biden administration and Danco argued that mifepristone might not be available for months if the restrictions put in place by the court in Texas were allowed to take effect.

The top court's action Friday will likely leave access to mifepristone unchanged at least into 2024, as legal appeals play out, including a potential appeal to the Supreme Court.

Conservative Justices Clarence Thomas and Samuel Alito dissented with the decision in the most significant abortion case to reach the nine-member court since it overturned the constitutional right to the procedure 10 months ago.

Since last year's Supreme Court decision, 12 US states enacted outright bans on abortion, while many others prohibit abortion after a certain length of pregnancy.

What is mifepristone?

The drug mifepristone has been approved for use in the United States since 2000, and more than 5 million people have used it. The FDA called mifepristone safe and effective, as demonstrated over decades of use by millions of people, adding that adverse effects are exceedingly rare.

Mifepristone is used in combination with a second drug, misoprostol, in more than half of all abortions in the US. The drug also has other uses, such as the management of miscarriages.