Russia is conducting covert mobilisation campaign, victory only possible through military force - Ukraine spy chief

Russia is using its reserve forces in a covert mobilisation to replenish its ranks in eastern Ukraine and there is no point in waiting for its offensive potential to simply fizzle out, the head of Ukraine's military intelligence agency said on Saturday.

In an interview in Kyiv, Kyrylo Budanov, told Reuters he believed Ukraine could only achieve a victory against Russia through military force.

"The strategy is very simple. Stabilise the situation. Receive the required amount of equipment and prepare the required amount of forces and means to start the counteroffensive to return all our territory," he said.

"We shouldn't wait for a miracle that they will tire and stop wanting to fight and so on. We will win back our territory as a result of our counteroffensive," said Budanov, head of the Defence Intelligence of the Ministry of Defence of Ukraine.

He stressed that a counteroffensive in Kherson will be difficult but that it is possible, adding that Ukraine should see visible results of it in the southern occupied region of Kherson from August.

"... from August we should expect visible results of military activity from Ukraine. Just wait a bit and we'll see what it brings," he said, when asked about plans for a counteroffensive in Kherson.

Russia seized control of the region at the beginning of its Feb. 24 invasion.

"As you see, there are already some events under way. They are not significant, but they are under way," he said.

He said the counteroffensive would hinge on various factors including Ukraine having a well-equipped enough concentration of forces, something that he added would depend on Ukraine getting help from foreign partners.

Budanov also said that Russia's operation in Ukraine involves 330,000 personnel, equal to a third of Russia's armed forces, a figure that includes technical staff as well as more than %50 of the Russian Army's combat forces.

He said was calm about the possibility of Russia eventually openly announcing a mobilisation as it would mean President Vladimir Putin having to face awkward questions at home.

"They really fear this - this is the main reason why the mobilisation is happening in a hidden way, particular by using (reservists)," he said.

"The military units that took part on Feb. 24 and those same military units now are in most cases on their second and in some cases even their third group of personnel," he said. "These are not the well-trained people who were prepared for many years."