Formally, this is a loan that is offered to be repaid. But in this situation, the parties can agree - to write off the loan in exchange for some concessions.

Okay, this is a deal. It's clear what Yanukovych got, but what is Putin's interest in it? (and please, don't start with the "saving the younger brother" again, it's not even funny anymore).
Formally, yes - it's a loan. But in reality, Yanukovych didn't care about all your formalities. He got what he wanted, and he was least concerned about who, how, and with what would pay for it. So, with this "help," Putin rather worsened relations with Ukraine than brought closer the bright moment of uniting brotherly peoples. What's the logic?

Added 8 minutes later
Oh yes, he bought time to put his insidious plan into action, what was I thinking...