"Lebanon is in free fall, it is a calamity happening in real time. We've seen this movie before and it is a horror story, but the good news is that it can, it should, and hopefully it will be avoided," Blumenthal said.
A financial collapse that began in 2019 hit a crunch point last month with a crippling fuel shortage that sparked security incidents and warnings of worse to come.
The financial crisis marks the biggest threat to Lebanon's stability since the 1975-90 civil war.
More than half of Lebanon's 6 million people have fallen into poverty. The World Bank says it is one of the sharpest depressions of modern times, with the currency plunging more than 90% and the financial system paralyzed.