Britain says Russian forces have not made advances in Sievierodonetsk, use anti-ship missiles

Russian forces around Ukraine's Sievierodonetsk had not made advances into the south of the city as of Friday, Britain's Defence Ministry said on Saturday.

"Intense street to street fighting is ongoing and both sides are likely suffering high numbers of casualties," the ministry said in an intelligence update posted on Twitter.

It also said that the Russian bombers have likely been launching 1960s-era heavy, anti-ship missiles meant to destroy aircraft carriers with nuclear warheads against land targets in Ukraine.

It said the 5.5-ton Kh-22 missiles, when used in ground attacks with conventional warheads, are highly inaccurate and can cause severe collateral damage and casualties.

Russia is likely using such weapons because it is running short of more precise modern missiles, Britain's Defense Ministry said in a daily update. It gave no details of where exactly such missiles are thought to have been deployed.

Russian forces have been concentrating their efforts on capturing all of Ukraine's eastern region of coal mines and factories known as the Donbas. The area borders Russia and has been partly controlled by Moscow-backed separatists since 2014.

Civilians have been fleeing intense fighting in eastern Ukraine as Russian and Ukrainian forces engage in a grinding battle of attrition for key cities in the country's industrial heartland.

The report said Ukrainian air defenses were still deterring Russian tactical aircraft from carrying out strikes across much of the country.