Russia plans to mobilize 500,000 soldiers in days. If they don't deliver victory, then 'Putin will collapse,' says Ukrainian spy chief.

• The Ukrainian military is warning that Putin is planning to mobilize up to half a million new troops.
• The Ukrainian Military Intelligence Service said that they believe the mobilization will be announced on January 15.

The Ukrainian military is warning that Putin is planning to mobilize up to half a million new troops in preparation for a new offensive in Ukraine.

Speaking to the German news site T-Online, Andriy Chernyak, a Ukrainian Military Intelligence Service representative, said that they believe the mobilization will be announced on January 15, after the Orthodox Christian Christmas.

Chernyak estimated 500,000 people would be mobilized, with those living in cities such as Moscow and St Petersburg to be most impacted.

Vadym Skibitsky, Ukraine's deputy military intelligence chief, said the recruits would be used in attacks that will begin in the spring in the east and south of Ukraine, reported the Evening Standard.

"We expect them to conduct offensives in Donetsk and Kharkiv regions, as well as possibly Zaporizhzhia but to defend in Kherson and Crimea, this is the number of men they will need for such a task," said Skibitsky.

"If Russia loses this time around, then Putin will collapse," said Skibitsky, according to reports.

The new infusion of manpower will massively increase the number of soldiers Russia has deployed in occupied Ukraine.

According to a Ukrainian official, there are currently 280,000 troops on the ground in Ukraine, per the Evening Standard.

A second mobilization has been discussed for months.

In November, Russian regional leaders wrote to Putin demanding he stops mobilizing reservists to fight in Ukraine.

Pro-Kremlin military bloggers in Russia have circulated claims that another mobilization will take place, according to the Institute of War.

Russia has dismissed reports that a second wave of mobilization was imminent and Putin claimed last month it was "pointless," reported The Guardian.

Russia's first mobilization in October of 300,000 soldiers was heavily criticized, with many mobilized soldiers being untrained, elderly, unwell, or too young to fight.

There have been reports of drunken brawls and indiscipline among the mobilized troops, with one recent incident resulting in the murder of a Russian military commander.