Belarus not the answer to Russia's lack of combat power

 ISW:

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Putin’s planned December 19 meeting with Belarusian President Alexander Lukashenko is likely part of the same effort to present proactivity as well as an effort to set information conditions for a new phase of the war. Commander of the Ukrainian Combined Forces Serhiy Nayev commented on the upcoming Putin-Lukashenko meeting and noted that it comes after Putin’s December 17 meeting with the Russian military command to discuss both immediate and mid-term goals for the war.[4] Nayev reported that the Ukrainian government believes Putin will discuss the wider involvement of Belarusian forces in further Russian aggression against Ukraine, which is consistent with ISW’s forecast for the meeting.[5] Taken in tandem, Putin’s meeting with the Russian command, Shoigu’s purported frontline visit, and the Putin-Lukashenko meeting suggest a new phase in the presentation, planning, and conduct of the war and may presage renewed offensive operations against Ukraine in the coming months.

The capacity of the Russian military, even reinforced by elements of the Belarusian armed forces, to prepare and conduct effective large-scale mechanized offensive operations in the next few months remains questionable, as other analysts have observed.[6] The manpower Russia is generating from mobilized reservists and from the annual fall conscription cycle will not be sufficiently trained to conduct rapid and effective mechanized maneuver this fall. Russia’s struggles to keep the forces it currently has fighting in Ukraine equipped with tanks, artillery, long-range strike, and other essential materiel are very unlikely to be resolved in time to equip a large new force for offensive operations this winter. Putin may nevertheless order renewed large-scale offensive operations later this winter, but it is important not to overestimate the likely capabilities of Russian or combined Russo-Belarusian forces to conduct them successfully. ISW continues to assess that it is unlikely that Lukashenko will commit the Belarusian military (which would also have to be re-equipped) to the invasion of Ukraine.
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Putin's irrational war efforts in Ukraine are unlikely to be salvaged by dragging in another weak power like Belarus.  At best he might get some equipment like that which was already ineffective in his Ukraine war. So far, Lukashenko has been wise enough not to put his own forces at risk for what is turning out to be one of the biggest military blunders in recent history.  If he does join the fray, he may find his country on the defensive.

See, also:

Vladimir Putin Visits Belarus as Ukraine Warns of New Offensive

Mr. Putin is in Minsk for talks with his Belarusian counterpart. Ukraine has warned that Russian forces could be preparing a new offensive from there.