And NS1 is under a contract that for all I know reads something like "Germany has an exclusive right to get as much gas as it wants through this pipe". So if Germany says "the amount we want is zero", Putler isn't going to sell any gas through NS1 for however long that contract is. But since Germany doesn't have any such deal on NS2, he could well write a contract to pump gas through NS2 to, say, Serbia or Hungary.