President Donald Trump boards Air Force One to return to Washington from Morristown Municipal Airport in Morristown, New Jersey, July 7, 2019.

The Trump administration has withdrawn its proposal to eliminate rebates from government drug plans, a key component of the president's blueprint to lower prescription drug prices, a White House spokesman confirmed.

"Based on careful analysis and thorough consideration, the President has decided to withdraw the rebate rule," White House spokesman Judd Deere said in an emailed statement Thursday.

Shares of health insurers jumped on the news. Cigna soared 9% and UnitedHealth rose 6%, while CVS Health, which bought insurer Aetna last year, closed up 5% on the day.

The administration sought to ban discounts on prescription drugs that insurers negotiate with pharmaceutical companies, saying these "backdoor rebates" have led to a "perverse incentive" for drugmakers to set list prices on drugs artificially high. Instead, the rule would give pharmacy benefit managers a flat fee for including drugs on their plan and would allow discounts to be passed on to patients at the pharmacy counter.