More than 16,000 civilians may have been killed since the start of the Ukraine war, according to UK intelligence.
Indiscriminate Russian shelling, which has seen severe damage to hospitals and schools, has contributed to the grim death toll, the Ministry of Defence (MoD) said.
The latest MoD update came as the first anniversary of the Russian invasion of Ukraine approaches.
Meanwhile, Vladimir Putin is set to address the Russian people in a major speech on the conflict.
The MoD said that as of February 13, the United Nations Office of the High Commissioner for Human Rights (OHCHR) had recorded 18,955 civilian casualties since the start of the war on February 24 last year.
That was made up of consisted of 7,199 deaths and 11,756 injuries. Some 697 of the civilian casualties occurred last month alone.
But the MoD added: “The OHCHR has stated it believes that the actual figures are considerably higher.
“Based on other, independent analysis, over 16,000 civilians have likely been killed.”
Last month saw a “worsening trend, of damage being inflicted on both medical and educational facilities”, the MoD said.
“These incidents, and continued civilian casualties are likely largely due to Russia’s lack of discrimination in the use of artillery and other area weapon systems.”
US president Joe Biden yesterday made a surprise visit to Ukraine to pledge his country's ongoing support to the country.
“When [Russian President Vladimir] Putin launched his invasion nearly one year ago, he thought Ukraine was weak and the West was divided,” Biden said in a statement released by the White House.
“He thought he could outlast us. But he was dead wrong.”