US Treasury Secretary Steven Mnuchin has made calls to the heads of the country's six largest banks, a move to reassure investors after huge falls in US stocks.
Last week, US stocks suffered one of the worst weekly falls in a decade as an interest rate rise and US-China trade tensions rattled markets.
Mr Mnuchin said banks confirmed they had "ample liquidity" for operations.
It also comes amid a partial government shutdown over spending plans.
"The [bank's chief executives] confirmed that they have ample liquidity available for lending to consumer, business markets, and all other market operations," the Treasury said in a statement attached to a tweet from Mr Mnuchin.
Today I convened individual calls with the CEOs of the nation's six largest banks. See attached statement. pic.twitter.com/YzuSamMyeT— Steven Mnuchin (@stevenmnuchin1) December 23, 2018
"[Mr Mnuchin] also confirmed that they have not experienced any clearance or margin issues, and that the markets continue to function properly," the Treasury's statement said.
All three US indexes closed lower last week, with the technology-focused Nasdaq down 20 percent since its peak, placing it in so-called "bear market" territory.
US investors are worried about a range of factors including slowing economic growth at home and internationally.
In addition, a partial US government shutdown began at midnight on Friday after opposition Democrats resisted President Donald Trump's demand for $US5 billion ($NZ7.4b) for his Mexico border wall.
The shutdown over budget spending could continue right up to the opening of the next Congress on 3 January.
Mr Mnuchin is now set to meet with the President's Working Group on Monday, the Treasury statement said.
The group includes market regulators and Federal Reserve governors, among others. They will discuss "coordination efforts to assure normal market operations", the statement said.