1. The contract was null and void is the same as saying there is no contract.
2. If you read what RusIvan said it's clear that if Ukraine had a contract that WASN'T null and void that they'd have been waving it in the Belgium arbitration court, instead they were afraid to go.
Since then they've made a deal which the Gas Princess Tymoshenko (who got rich stealing Russian gas) objects to. Hmm isn't in interesting that a deal that prevents Ukraine from stealing gas is objected to by the one who profited most from stealing it.
"if Ukraine had a contract that WASN'T null and void that they'd have been waving it in the Belgium arbitration court,"
What, do you think a suit in the Hague is like walking into McDonalds? First you have to get world opinion against Putie and then you crush his nuts in court.