Hong Kong stocks declined on Tuesday as investors assessed the latest developments in U.S.-Iran negotiations while bracing for a more hawkish Federal Reserve.

The Hang Seng Index fell 1.8%, or 432.24 points, to close at 23,336.28. The Hang Seng China Enterprises Index dropped 2.0%, or 155.38 points, to finish at 7,759.36.

The United States waived sanctions on Iran for 60 days beginning Monday following an initial round of talks under a fledgling peace agreement.

U.S. President Donald Trump said he would "do what I have to do" if Tehran failed to uphold its commitments.

Meanwhile, traders are increasingly betting on a faster pace of monetary tightening under new Federal Reserve Chair Kevin Warsh.

Markets expect the Fed to deliver a total of 50 basis points of rate hikes by year-end to combat inflation pressures, particularly from higher energy costs, Reuters reported, citing CME Group's FedWatch Tool.

In corporate news, two companies made their trading debut on the Hong Kong bourse.

HJ Science (HKG:6132) closed 57% lower at HK$35.26, compared with its offer price of HK$81.80.

Shenzhen Senior Technology Material (HKG:6067, SHE:300568) advanced 22% to HK$11.00, versus its offer price of HK$8.98.