US President Donald Trump says he will "not even consider" renaming military bases named for Confederate generals.
He tweeted that the bases were part of "a Great American heritage".
Mr Trump's remarks follow reports that top military officials were open to changes amid nationwide soul-searching after the death of George Floyd.
For many, symbols of the Confederacy – the slaveholding southern states that seceded, prompting the 1861-65 American Civil War – evoke a racist past.
The move to rename the 10 bases named for Confederate generals – all located in former Confederate states – has been presented by advocates of the idea as a step towards racial reconciliation.
On Wednesday, Nascar – a league in which both drivers and fans are overwhelmingly white – announced that it would ban the flying of Confederate flags at its races and other events.
And earlier this week, the US Marine Corps issued an order for commanders to "identify and remove the display of the Confederate battle flag or its depiction within workplaces, common-access areas and public areas on their installations".
But Mr Trump rejected this cultural shift, writing in a tweet that the bases named for Confederate generals "have become part of a Great American heritage, a history of Winning, Victory and Freedom".
He added: "The United States of America trained and deployed our HEROES on these Hallowed Grounds, and won two World Wars. Therefore, my Administration will not even consider the renaming of these Magnificent and Fabled Military Installations.
"Our history as the Greatest Nation in the World will not be tampered with. Respect our Military!"
The bases are located across the US South, in states that fought for the Confederacy, and include well-known installations such as Fort Bragg in North Carolina, Fort Hood in Texas and Fort Benning in Georgia.
Many of those states helped deliver Mr Trump's victory in 2016, and he is relying on them again to support him in November's election.