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Russian troops are about 15 kilometres from Kyiv's city centre but are moving their support elements closer, the Pentagon assessed on Friday.
A senior US defence official briefing reporters said Russian troops stationed north-west of Ukraine’s capital “have not moved any closer” and are the same distance as they were yesterday.
But the official noted that the Russian military's support elements are edging closer to Kyiv.
Asked about Russia's 64-kilometre-long convoy outside the city, the Pentagon said it now believes it is being dispersed and disguised in forested areas to protect it from Ukrainian attacks.
“We do not believe the convoy has made any progress in linking up with other elements,” the US defence official said.
US satellite company Maxar said on Thursday evening that the convoy is now “largely dispersed and redeployed".
Elsewhere in Ukraine, the US defence official said Russia has not taken the city of Kharkiv but is “closing in” after weeks of heavy bombardment.
“We're seeing more reports of internet outages there,” the US official said.
The internet monitor Netblocks reported that the Kharkiv Institute of Physics and Technology has gone offline after a Russian attack on Thursday night.
But the Pentagon assessed that Russia is still facing stiff resistance from Ukraine in the city as well as in Mariupol where Moscow has conducted more air strikes.
The official estimated “that the Russians, writ large, are flying on average 200 sorties per day” across Ukraine.
In contrast, the official said Ukraine has about 56 fighter jets remaining and are flying five to 10 sorties a day, while relying on other weapons such as anti-tank and anti-aircraft missiles.
Washington has rebuffed Poland’s proposal to send Ukraine Soviet-era MiG-29 fighter jets in return for supplying Warsaw with more advanced F-16 planes from the US.
On Thursday, the Pentagon also rejected sending Patriot missile systems to Ukraine, as it would require the deployment of US troops on the ground to operate them.
“It's not a system that the Ukrainians are familiar with. And as we have made very clear, there will be no US troops fighting in Ukraine,” the official said.
Asked about Russia’s announcement on Friday that it is sending 16,000 volunteer troops from the Middle East to fortify its forces in Ukraine, the Pentagon said it has no indications that such effort has materialised.
“We haven't seen any indications their recruiting efforts have borne fruit,” the official said.
