Economic sanctions are primarily made to stop a certain nation's economic activity in face of an adverse action caused by a nation. And nations primarily using this process are western nations with huge economic resources like U.S. and it could have devastating consequences as seen in multiple cases such as Cuba or North Korea and even Russia.
But, how large will be the impact of an economic sanction on a nation if the economic sanction is imposed by China and India as they are the 2nd and 5th largest economies of the planet with combined GDP of 13.46 trillion dollars (72% of U.S.A's GDP) which shows that US is not the only nation with the economic might to impose economic sanctions on nations. China alone has a Forex reserve of over 3 trillion $ , which is 1 trillion dollar more bigger than GDP of U.K. or France.