President Donald Trump announced a plan Tuesday he says will drastically reduce the price of insulin for people on Medicare -- relief he tied directly to his own political prospects, saying he hoped "the seniors are going to remember it."

The message came amid a coronavirus pandemic that has most directly affected older Americans. Trump's support among older voters has softened during the outbreak, worrying some of his advisers and leading to renewed efforts at the White House to highlight support for senior citizens.

The announcement on Tuesday fit within that. Trump said most senior Medicare recipients will be able to get prescription plans that cap copay costs for insulin, allowing them access to various types of insulins at no more than a copay of $35 for a month's supply.

Trump unveiled details about the new Medicare benefit during a Rose Garden news conference on Tuesday accompanied by the heads of insulin manufacturers Eli Lilly and Novo Nordisk, as well as insurance representatives and the American Diabetes Association.

"Today I'm proud to announce that we have reached a breakthrough agreement to dramatically slash the out-of-pocket cost of insulin," Trump said. "You know what's happened to insulin over the years, right? Through the roof."

Trump also used the announcement to disparage former Vice President Joe Biden, his likely 2020 Democratic opponent, claiming that "Sleepy Joe can't do this, that I can tell you."

"I hope the seniors are going to remember it," Trump said of the new policy, "because Biden is the one that put us into the jam because they didn't know what they were doing, they were incompetent."

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Senior citizens are among the country's most reliable voters and voted for Trump by a 7-point margin in 2016. But a CNN poll conducted by SSRS earlier this month found 56% of respondents over the age of 65 disapproved of Trump's handling of the outbreak, compared to 42% who approved. That was the lowest approval of any age group except those between 18 and 34.

The same poll showed 57% of registered voters over 65 would vote for Biden if the presidential election were held today, versus 42% who said they would vote for Trump.

The falloff has concerned some of Trump's political advisers, and the White House has sought to highlight the President's efforts to combat the virus in nursing homes and among senior citizens.

In his remarks, Trump also thanked Seema Verma, administrator of the Centers for Medicare and Medicaid Services, for having "brought this to my attention a long time ago."

Verma said during a call with reporters earlier on Tuesday that "these plans will begin starting in January 2021 in all 50 states, DC and Puerto Rico, and seniors can find a participating plan on our 'Medicare plan finder' during the annual open enrollment period, which begins on October 15."

The new benefit will be offered through Medicare Part D prescription drug plans and Medicare Advantage plans.

"That results in approximately a 66% or two-thirds reduction in out-of-pocket costs," White House counselor Kellyanne Conway said during the call with reporters.

The move comes as lawmakers across the US have begun a push to cap the cost of insulin after years of skyrocketing prices. Virginia, Illinois and Colorado have passed bills setting payment caps on the drug, with Tennessee lawmakers considering a similar bill. Insulin costs between $2.28 and $3.42 for drug makers to manufacture, yet many people with diabetes pay hundreds of dollars for the lifesaving drug.

CMS noted in a press release on Tuesday that more than 1,750 standalone Medicare Part D prescription drug plans and Medicare Advantage plans with prescription drug coverage have applied to offer lower insulin costs through the Part D Senior Savings Model for the year 2021.

Verma added during Tuesday's call that CMS will monitor the results of this approach to lowering insulin costs and, if the model proves successful, will expand it to other high-cost drugs.

"We're starting with insulin, but depending on the progress of this, we will consider offering this flexibility to manufacturers and plans with other drugs, depending on the results," Verma said. "We think that this creates a foundation and a platform to fixing some of the problems that we have in the Part D plan. It's time for that program to be updated."