Like I said anyone is free to do what they want. Was just explaining how such line probably doesn't exist. You know how Russia got sanctioned and countries are not allowed to buy and sell from it anymore? Similar to Cuba. Etc. If you see no problem with it fine but you know you are helping a country that is invading another. Some people rather not to be part of it.
Same thing about drugs, if you buy drugs you are helping the system of it, aka cartels that are a bunch of murderes.
"Countries are not allowed to buy or sell from Russia".
USA is buying fertilizers from Russia and some radioactive elements.
Europe is buying Gas and other stuffs.
Asia is buying oil with China and India leading it and interestingly, USA after imposing sanctions asked India to buy oil from Russia to stabilize energy market.
And, let me tell you something really interesting - Russian oil gets refined in India.
And, you know who is the largest supplier of diesel to Ukraine?
India is...in short, ukraine is indirectly getting diesel from Russia to use in the war against Russia.