The speed and success of the Ukrainian offensive has taken their own forces by "surprise".
Former Royal Marine and documentary-maker Emile Ghessen has been in the Kharkiv region with Ukrainian Forces as they conducted a counter-offensive which saw them take back large amounts of territory captured by the Russians across Kharkiv and also in Kherson.
The former Royal Marine told Forces News: "The Ukrainian soldiers are very surprised with how quick they are clearing villages, towns, all the way up to the Russian border and towards Donbas region."
"We'll see you in Crimea, we'll see you in Moscow"
Russian forces have sustained heavy losses since the invasion of Ukraine began in February, and sanctions have restricted access to key components of its weapons systems.
The Ministry of Defence (MOD) intelligence recently reported that "Russia is almost certainly increasingly sourcing weaponry from other heavily sanctioned states like Iran and North Korea as its own stocks dwindle".
Ghessen added that among the Ukrainians "the morale is very high".
"There's lots of talks of victory before winter, which I think is very premature at this moment in time, but they are talking about 'we'll see you in Crimea and we'll see you in Moscow'.
"Very much amongst the Ukrainians, the morale is very high," he added.