It is naive to think that fuel supply would continue to be guarenteed in the event of India going for another test. Whether India should go for another test is a seperate matter al together. And if India decides to test another, it will have to be prepared for 'sanctions'.
If we have the right leaders at the top, then the decision to 'test' will take into account the consequences. May have to guarentee that India has enough stock and technology even if the deal is to be called off.