President Donald Trump speaks during a rally in El Paso, Texas on February 11, 2019.Nicholas Kamm | AFP | Getty ImagesPresident Donald Trump signed an executive order Thursday that he said would improve private Medicare plans for seniors, slamming Democrats for what he described as putting health care “under threat” with “Medicare for All” proposals.Trump, speaking for an hour at a campaign-style rally at a retirement community in Florida, offered few details on his executive order and spent most of his speech attacking the health policies of 2020 Democratic presidential contenders. He said as long as he’s president, “no one will lay a hand on your Medicare benefits.””Medicare is under threat like never before,” Trump told the crowd. “I will never allow these politicians to steal your health care and give it away to illegal aliens.”Shortly after Trump’s speech, Health and Human Services Secretary Alex Azar said the president has “directed HHS to take a number of specific, significant steps that will meaningfully improve the financing of Medicare, advance the care American seniors receive from their doctors, and improve the health they enjoy.”Azar said those steps including lowering costs in Medicare Advantage, allowing those beneficiaries to create savings accounts and accelerating access to the latest medical technologies after being approved by regulators.Earlier Thursday, senior administration officials said Trump was expected to issue an executive order making changes to the Medicare program to “protect” Americans from Democratic health-care proposals they said would “destroy” coverage for seniors.The executive order is intended to bolster Medicare Advantage, which is private Medicare insurance for seniors, the officials said on a call with reporters. The plan would also offer more affordable plan options, encourage wider use of telehealth services and bring payments in Medicare fee-for-service program in line with payments for Medicare Advantage, officials said.Watch: Trump has made lowering health-care costs one of the key issues of his administration as health care remains a top issue for voters in the 2020 elections.The executive order takes direct aim at 2020 Democratic candidates who advocate for changes to the U.S. health-care system through some version of Medicare for All.Arguably the most drastic proposal is from Sen. Bernie Sanders, I-Vt., who is calling for eliminating private health insurance and replacing it with a universal Medicare plan. Proponents say it would help reduce administrative inefficiencies and costs in the U.S. health-care system. Sen. Elizabeth Warren, D-Mass., has backed Sanders’ proposal.During the speech in Flordia, Trump described “Medicare for All” as a massive “government health-care takeover” that would “obliterate” coverage for seniors.”They want to raid Medicare to fund a thing like socialism,” he said. “Today we’re creating a health-care system that protects vulnerable patients.”Spokespersons for Sanders’ and Warren’s campaigns did not respond to requests for comment.