Unpaid bills, failure to pay due bills, as defined in their legally binding financial agreement to supply gas.
Failure to pay bills, according to legally signed, binding agreement leads to consequences, personal, commercial and international. Business is business my boy.
2009 Russia–Ukraine gas dispute
"The 2009 Russia–Ukraine gas dispute was a pricing dispute between Russia and Ukraine that occurred when Russian natural gas company Gazprom refused to conclude a supply contract for 2009 unless Ukrainian gas company Naftogaz paid its accumulating debts for previous gas supplies"
From your source:
https://en.wikipedia.org/wiki/2009_R...ne_gas_dispute
Not political, not as a weapon. Another lie from yourself.
Try reading your source again.