It is "absurd and shameful" that a statue of Winston Churchill has had to be boarded up because of fears it could be vandalised, the prime minister says, APA reports citing BBC.
Boris Johnson said the war-time leader had expressed opinions which were "unacceptable to us today" but remained a hero for saving the country from "fascist and racist tyranny".
Protesters daubed "was a racist" on the monument last weekend.
Labour said the PM should "show leadership" by addressing the nation.
Shadow home secretary Nick Thomas-Symonds told the BBC he wanted to hear that Mr Johnson "understands the deep hurt and anger that black people in our country feel".
In a series of tweets, Mr Johnson said monuments like Churchill's were put up by previous generations as he urged people to "stay away" from demonstrations amid the coronavirus pandemic.
"We cannot try to edit or censor our past," he wrote of moves to remove tributes to historical figures. "We cannot pretend to have a different history."
The statue in London's Parliament Square was boxed up ahead of a Friday evening Black Lives Matter protest in Westminster.
A demonstration planned for Saturday was brought forward by a day because of fears there could be violent clashes with far-right groups.
Leaders of the march urged those in attendance to keep the demonstration "peaceful" and not to join any anti-racism rallies planned for the weekend.
Hundreds of campaigners surrounded Nelson's Column in Trafalgar Square by 17:00 BST after walking from Hyde Park, as around two dozen police officers watched on.
Other monuments have been removed ahead of separate protests planned over the weekend, while the Cenotaph war memorial, in nearby Whitehall, has also been covered.
In Poole, Dorset, a statue of Scouts movement founder Robert Baden-Powell is to be cladded instead of removed.