Proposed sanctions and cutting ties with Russia in energy sphere (in particular, delivery of vital sophisticated technology) would be really painful for many European countries, Italy, the UK and other. UK's energy giant BP is alarmed by the possibility 'cause it owns more than 20 percent of Russia's state owned Rosneft. I know that BP CEO Bob Dudley has recently assured shareholders that the company will keep business with Russia "as usual'.
I think such phrases must bring to senses some USA hawkish politicians so much hateful of Russia and caring a sh-t about Europe's needs! I'm 100 percent sure that if they stick to the line they risk to strongly undermine the basement of long-standing relationship between the USA and Europe.
Mind also that most EU countries are still feeling feeble slowly getting back to normal after the worst crisis in decades. It can't be missed on the USA. What if America is just set to weaken her European ally and get away some promising markets from it?