I may be wrong, but this is probably a deliberate set-up by the Russians placing his chair farther away, to force him into a more uncomfortable position.
If this is true, it is a commentary on the differences between the relationship between Russia and China and the relationship between Russia and India.
That is over intepretation. The Indian guy is just nervous or lack of manner. The chair isn't bolted to the floor, there is no way to hinder pulling it closer. Besides, the chair has arm supports, it has to be put further away to the table than chairs without arm support before seating. After seated it is either the guest himself pulling it forward, or some valet do it.
Even if it is difficult to move it, a proper action is just sit where it is, not trying to put arms on the table. Leaning forward shows attention, eagerness or aggression, not being relaxed.
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If you look carefully, Shoigu's chair has no arm supports, that is one rank lower than Putin's and the guest's chairs. Russians have attended to the very detail of diplomatic protocal in good intention.
Those chairs are probably heavy, likely he couldnt move them himself
Nah, those antique chairs are made of oak frames, the heaviest wood used in furniture in the past centries, with the seating cushion and back cushion suspended by some fabrics or ropes. They are heavier than today's Ikea chairs but not much, even if dragged over carpet.