As many as 500,000 Russian soldiers may be called into a new military mobilization in Russia, according to Ukraine.

And the announcement may come soon – as early as January 15.

The data is seen as a sign that President Putin is planning an escalation in the war of invasion that has now been going on for barely a year.

"Planning an offensive this spring"

According to Vadym Skibitsky, head of Ukraine's intelligence service, the expected mobilization is part of an expanded offensive against the eastern and southern parts of Ukraine this spring and summer.

President Zelensky has also warned:

"There is no doubt that the Russian leaders will throw everything they have into trying to turn the tide of the war, or at least postpone their defeat," he said recently.

According to Katarina Engberg, security policy analyst and senior advisor at the Swedish Institute for European Political Studies, there are several signs that point to an upcoming gathering of forces in the Russian army.

- They don't just talk about more manpower, but change the industry and call on the Russian people to stand up behind the heroes at the front.

Everything points to planning for an offensive in the spring, she says.

"Eating into Russian society"

Russian Defense Minister Sergei Shoigu said on December 21 that Russia plans to expand its army by a third - to a force of 1.5 million.

In addition, the Kremlin has started to talk about shortcomings and losses in the war against Ukraine - which is not usual.

- It is a new way of talking about the war and it is used to appeal to the Russians to stand up.

Now it is no longer a special operation to be handled by anyone other than the Russian people.

This has begun to eat into Russian society.

Putin denies

Putin rejects the information about mobilization and has called it "meaningless", especially since Russia is alleged to have called up only half of the soldiers who were part of the mobilization last autumn.

He denied plans for mobilization last year as well, before announcing in September that 300,000 conscripts were being drafted into the war.