A federal judge in Arkansas has issued a two-week temporary restraining order stopping an Arkansas law that would restrict the use of the so-called abortion pill.

U.S. District Judge Kristine Baker granted the restraining order on New Year's Eve, a day before the law, Act 577, also known as the "Abortion-Inducing Drugs Safety Act," was set to take effect.

The decision was based on the challenge by Planned Parenthood of Heartland, which operates clinics in Arkansas, according to Reuters.

In her ruling, Baker said Planned Parenthood has a chance to win its argument that the law is unconstitutional since it infringes on a woman's right to abortion.

The law requires an abortion service provider to "have a signed contract with a physician who agrees to handle complications," who also should have admitting privileges at a hospital.

The judge said Planned Parenthood has "a substantial likelihood of success on their argument that this portion . . . would result in an undue burden and would have the effect of placing a substantial obstacle in the path of a woman's right to choose to have an abortion of a nonviable fetus."

Attempts to restrict abortion have intensified in recent years in Arkansas as Republicans took control of the state's legislature and the governor's office last January.

The state now requires pre-abortion counselling and a 24-hour waiting period before the procedure.

Under the law, passed last March, organisations or individuals dispensing mifepristone are required to have a contract relationship with a physician with admitting privileges. It also requires a patient to receive more doses of the drug than the four presently required by law.

Mifepristone is taken to induce miscarriage when taken in the first two months of pregnancy.

Planned Parenthood said the extra dosage is clinically unnecessary and imposes undue financial burden. It said it tried to contract physicians but they feared to enter into a relationship with Planned Parenthood for fear of reprisals.

"At this early stage of the proceeding, the court finds that, in the case of medication abortion, any benefit of admitting privileges in terms of continuity of care is incrementally small," Baker wrote in her decision.

She also said the extra dosage was based on "inaccurate, incomplete, irrelevant, or outdated" data. Arkansas said the law was meant to protect women's health.

Governor Asa Hutchinson accused Planned Parenthood of placing "a premium on the convenience of abortion providers over the health and welfare of women seeking these procedures."