Washington | The US Supreme Court has shot down a controversial Louisiana law that would have left the state with only one abortion clinic, in a blow to those who hoped US President Donald Trump's two conservative appointees would see the court reverse five decades of established law on access to the procedure.

In a five-to-four decision, Chief Justice John Roberts backed the court's liberal justices, arguing that the Louisiana law was invalid because it was similar to a 2016 Texas law that was also overturned.