(CNN) The Trump administration has the authority to make it easier to buy a less expensive alternative to Obamacare coverage, a federal judge ruled Friday.

The lawsuit, brought by a coalition of non-profit insurers that sell plans on the Affordable Care Act exchanges and by patient assistance groups, centers on the administration extending the duration of short-term health insurance plans to just under one year, instead of three months. The rule, which was issued last year, stems from an executive order President Donald Trump issued in the fall of 2017.

"Plaintiffs have strived mightily to frame the 2018 rule as such an 'extraordinary' administrative action, striking a blow to the heart of the ACA in a manner that is both unprecedented and unworthy of judicial deference," Judge Richard Leon of the US District Court for the District of Columbia wrote in his decision . "Unfortunately for the plaintiffs, neither the law nor the facts supports that conclusion."

The ruling represents a win for the administration, which recently has suffered a string of setbacks in court over its efforts to chip away at the Affordable Care Act and to reduce health care costs.

Short-term plans, which have been available for years and were originally designed to fill a temporary gap in coverage, are typically cheaper than Obamacare policies. But that's because they are allowed to exclude those with pre-existing conditions and base rates on an applicant's medical history, unlike Obamacare plans.

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