A state judge has shielded, for now, Texas abortion clinics from lawsuits by an anti-abortion group under a new state abortion law in a narrow ruling.

The temporary restraining order on Friday by state District Judge Maya Guerra Gamble in Austin in response to the Planned Parenthood request does not interfere with the provision. 

However, it shields clinics from whistleblower lawsuits by the non-profit group Texas Right to Life, its legislative director and 100 unidentified individuals.

A hearing on a preliminary injunction request was set for September 13.

The law, which took effect on Wednesday, allows anyone anywhere to sue anyone connected to an abortion in which cardiac activity was detected in the embryo — as early as six weeks into a pregnancy before most women even realise they are pregnant.

In a petition filed late Thursday, Planned Parenthood said about 85% to 90% of people who obtain abortions in Texas are at least six weeks into pregnancy.

The order "offers protection to the brave health care providers and staff at Planned Parenthood health centers throughout Texas, who have continued to offer care as best they can within the law while facing surveillance, harassment, and threats from vigilantes eager to stop them," said Planned Parenthood spokeswoman Helene Krasnoff in a statement.

However, the order will not deter Texas Right to Life's efforts, said Elizabeth Graham, the group's vice president. In a statement, the group said: "We expect an impartial court will dismiss Planned Parenthood's lawsuit. Until then, we will continue our diligent efforts to ensure the abortion industry fully follows" the new law.

Biden calls Texas abortion law 'vigilante' justice

Meanwhile, President Joe Biden on Friday called a measure in Texas encouraging the public to enforce severe new abortion restrictions "vigilante" justice.

"The most pernicious thing about the Texas law is it sort of creates a vigilante system, where people get rewards," Biden said at the White House, adding the measure "sounds ridiculous, almost un-American."

Under the law, anyone living in Texas can sue an abortion provider or anyone suspected of "aiding" an abortion to take place, with $10,000 rewards if they win in a civil case.

Biden said there may be existing legal avenues "to limit the independent actions of individuals in enforcing… a state law," but did not explain further.

A Roman Catholic who is criticised by anti-abortion activists for supporting abortion rights, Biden added of his opponents: "I respect their views."