Keeping a legal challenge to the Affordable Care Act on a fast track, a federal appeals court Tuesday rejected a request to delay next week's oral arguments made by Texas and 19 other states seeking to overturn the law.

The Republican attorneys general, including Ken Paxton of Texas, said they needed more time to research and respond to questions — recently posed by the 5th U.S. Circuit Court of Appeals' three-judge panel — that could end the appeal and provide a victory for opponents of the law.

With that response due Wednesday, Texas Solicitor General Kyle Hawkins, the top appellate lawyer in Paxton's agency, asked for 20 additional days to submit the brief, with oral arguments to be reset for sometime afterward.

The appeals court rejected the request but pushed the deadline back two days, giving all sides until 5 p.m. Friday to submit the requested briefs.

The delay was opposed by Democratic-led states and the U.S. House, which are fighting to preserve the Affordable Care Act after a federal judge in Texas — based on a lawsuit filed by Paxton — ruled in 2018 that the law was unconstitutional.

"Allowing this appeal to proceed on its current schedule will provide some measure of certainty about the ACA’s future to states, the health care system — including providers and insurers — and ordinary Americans, and allow them to structure their affairs accordingly," the Democratic lawyers told the court.

The law, sometimes known as Obamacare, remains in effect during the appeal.

Although the U.S. Justice Department will argue in favor of striking down the law, its lawyers opposed delaying oral arguments in the case, although the department would have agreed to postpone filing the requested briefs until a day before Tuesday's arguments, Hawkins told the court.

The Justice Department had earlier asked to speed up consideration of the case, and the appeals court agreed, setting a July date to hear the matter.

Last week — almost five weeks after scheduling the argument date — the appeals court raised several late questions and gave lawyers seven days to answer them:

• Do the Democratic-run states and the U.S. House have standing to appeal the ruling that struck down the Affordable Care Act, and did the House act in time to intervene?

• If the parties lack standing, is there a "live case or controversy" for the court to pursue?

• What would be the "appropriate conclusion" to the case if nobody has standing to appeal?

"The attorneys should also be prepared to address these questions at oral argument," the court said.

Supporters of the law viewed the request with alarm, noting that the lower-court ruling would stand if the appeal was tossed out on procedural grounds.

In the request for a delay filed late Monday, Hawkins told the court that it was unlikely the states could have their answers completed in time.

"These important and potentially dispositive questions merit a thorough response that represents the cohesive views of (the) states and their respective attorneys general," he wrote.

Paxton has argued that Congress rendered the Affordable Care Act unconstitutional when it removed the law's financial penalty under the individual mandate — which requires most taxpayers to have health insurance — as part of President Donald Trump's tax cuts in 2017.

In December, U.S. District Judge Reed O'Connor agreed, ruling that without a tax penalty, the act was not a proper exercise of congressional tax power and was therefore unconstitutional.

California and other Democratic-led states appealed, followed by the U.S. House, arguing that O'Connor's ruling was wrong on the law, would throw the U.S. health care system into havoc and improperly used the courts to overturn the Affordable Care Act, something congressional Republicans failed to accomplish more than 70 times since the law was enacted in 2010.