Benchmark Dalian and Singapore iron ore futures surged on Thursday, buoyed by growing hopes of improved demand for the steelmaking ingredient in China after reports of a possible easing of COVID-19 curbs in the world's top steel producer.

The most-traded May iron ore contract on China's Dalian Commodity Exchange climbed as much as 9.7% to 818.50 yuan ($129.54) a tonne, advancing for a fourth straight day to its highest since Feb. 11.

On the Singapore Exchange, the front-month April iron ore jumped 8.9% to a contract high $162.40 a tonne.

"The whole China ferrous futures complex is reacting zealously to reports that the country is contemplating exiting its 'zero-tolerance' stance towards COVID-19, for which the 'stop/start' impact on the economy has been a heavy burden," said Atilla Widnell, managing director at Navigate Commodities in Singapore.

"Fewer intermittent lockdowns will support China's pursuit to getting the economy back on track."

In the spot market, imported iron ore traded at $147.50 a tonne on Wednesday, the highest since Feb. 14, according to SteelHome consultancy data.

"While the Russia-Ukraine war has displaced 70 million tonnes of iron ore exports almost overnight, it will mainly be the blast furnace pellet market - 138 million tonnes in 2021 - which feels the immediate wrath of tighter supply given that these two countries account for 29 million tonnes, or 21%, of global seaborne trade," Widnell said.

Chinese steel futures and other steelmaking ingredients also extended what appeared to be another blistering rally after market regulators last month sought to curb surging prices of iron ore and coal in particular.

Hot-rolled coil, which is steel used in car bodies and home appliances, on the Shanghai Futures Exchange rose 3% to its highest since October.

Construction steel rebar gained 1.9% to its strongest since Feb. 11. Stainless steel was up 2.9%.

Dalian coking coal climbed 3.8% and coke advanced 3.3% to their strongest levels since October.