The U.S. Treasury is advising banks to be on the lookout for suspicious financial activity involving corrupt Venezuelan officials as the Trump administration tightens its financial noose around President Nicolas Maduro's embattled socialist government.

Wednesday's advisory by the Financial Crimes Enforcement Network asks banks to keep watch for Venezuelan government contracts, wire transfers from shell companies and real estate purchases in south Florida and Houston by senior Venezuelan officials, their families or associates. It said the advisory arose out of concern expressed by financial institutions that transactions involving state-owned enterprises were being used to launder kickbacks and bribes.

U.S. officials fear that endemic corruption will take an additional toll on Venezuelans already struggling with triple-digit inflation and widespread shortages amid a tense political standoff aggravated by Maduro's decision to rewrite the constitution in the face of months of deadly protests.