The UK has said the majority of Russian forces are about 18 miles or 30 km from the centre of Kiev, The Guardian reported.
In an intelligence update by the Ministry of Defence posted on Saturday morning, it said Russia had yet to gain control of airspace over Ukraine, reducing the effectiveness of the Russian air force.
It added: "Russian casualties are likely to be heavy and greater than anticipated or acknowledged by the Kremlin."
Also Read | Battle for UP: Polling begins for 5th phase including Ayodhya, Amethi
Russia claims it has taken the southeastern city of Melitopol which was denied by the UK armed forces minister, James Heappey, who said he did not recognise the reports and said the Russian invasion plan was running "nowhere near" to schedule, The Guardian reported.
The UK government armed forces junior minister said Russia has failed to achieve its initial objectives -- and fighting outside Kiev was limited to Russian special forces units, The Guardian reported.
Speaking to BBC Radio 4's Today programme, James Heappey said that aims to take key Ukrainian cities had not been successful.
Also Read | Ukraine conflict will last, says Macron as France braces for economic impact
He added that the UK did not believe Russian claims that it had taken the south eastern city of Melitopol.
"The Ukrainian resistance to the Russian advance appears extraordinary. All of Russia's Day One objectives of Kharkiv, Kherson, Mariupol, Sumy and even Melitopol, which the Russians are claiming to taken but we can't see anything on that, are still all in Ukrainian hands," The Guardian reported.
"The fighting on the outskirts of Kiev overnight, we understand to just be Russian spetsnaz special forces and pockets of paratroopers. The reality is the armoured columns coming down from Belarus and the north to encircle Kiev are still way off, because they have been held off by this incredible Ukrainian resistance," the report added.
