Before this announcement, even the countries that hate US had no choice but to use US Dollar for Oil trade, how Ironic it is that you hate me but put your hard earned money towards the purpose of me controlling you. With this action, China has given an alternate to those nations. In the short term this wont make a big dent in the US dollar domination but and small scratch but in the long run it will help countries to get out of US choke hold. US Sanctions wont have any effect since there is an alternate route that goes thru China.