CARACAS, Venezuela — Two nephews of Venezuela’s powerful first lady are facing arraignment in New York after being arrested in Haiti on charges of conspiring to smuggle 800 kilograms of cocaine into the U.S., people familiar with the case said.

The arrest of Efrain Campos and Francisco Flores is likely to exacerbate already tense relations between the U.S. and Venezuela and cast a hard look at U.S. accusations of drug trafficking at the highest levels of President Nicolas Maduro’s socialist administration.