U.S. stock index futures fell on Thursday on worries of a global economic downturn from aggressive interest-rate hikes by central banks and risks of a potential contagion from a turmoil in UK markets.

The Dow and S&P 500 e-minis fell for the seventh time in eight sessions, while megacap growth names such as Amazon.com Inc, Apple Inc, Microsoft Corp , Meta Platforms Inc and Tesla Inc lost between 0.9% and 2.1% in premarket trading.

The calm brought about by the Bank of England's decision on Wednesday to buy long-dated government securities to stabilize the turmoil in the markets caused by the government's new economic plan was short-lived.

Sterling fell and bond prices slid, with the selloff in British assets spilling over to even safe-haven U.S. Treasuries and top-rated German bonds.

Even though U.S. stocks ended sharply higher in previous session due to easing Treasury yields, they have been battered for a large part of the year as surging yields dented the appeal for stocks.

"The world is transitioning from a low interest rate environment to a high interest rate environment," said Andrea Cicione, head of strategy at TS Lombard.

"The market is repricing macro risks and the catalyst obviously this year has been the Fed and other central banks starting to hike rates... The question about debt sustainability and funding countries with current account deficits has become extremely real."

The yields on many Treasuries, which are considered virtually risk-free if held to maturity, now dwarf the S&P 500's dividend yield, which recently stood at about 1.8%, according to Refinitiv Datastream.

American Airlines fell about 1% as carriers canceled almost 2,000 U.S. flights for Thursday after Hurricane Ian hit Florida's Gulf Coast with catastrophic force in one of most powerful U.S. storms in recent years.

Share of peers United Airlines Holdings, Southwest Airlines and Delta Air Lines fell between 0.1% and 1.1%.

U.S. cruise companies Norwegian Cruise Line Holdings Ltd and Carnival Corp fell 1.6% and 1.9% after they delayed or canceled trips in anticipation of the hurricane.

Investors will be watching for weekly jobless claims, which is expected to rise by 2,000 to 215,000 last week. Final economic growth figures for the second quarter are also due.

A second estimate of the government last month had shown the economy contracted at 0.6%, a more moderate pace than initially thought.

Comments from the Federal Reserve's Cleveland President Loretta Mester on inflation will also be on the investor watch-list.

(Source:Investing.com)