* Dalian iron ore drops 3%, Singapore futures down 2.3%
* Rio Tinto (LON:RIO) says Shanghai team returning to office
* Fortescue says mining, shipping activities continue
By Enrico Dela Cruz
MANILA, March 30 (Reuters) - Iron ore futures in China and Singapore fell on Monday on renewed doubts whether the massive stimulus measures introduced across the world are adequate to buttress a global economy hammered by the coronavirus pandemic.
Worries about demand for metals also hit steel futures in China, which accounts for more than half of the world's steel output and the top exporter of steel products.
The Dalian Commodity Exchange's DCIOcv1 most-active May contract for steelmaking ingredient, iron ore, dropped as much as 3% to 640.50 yuan ($90.26) a tonne, before ending the morning session down 2.8%.
Iron ore's front-month April contract on the Singapore Exchange shed as much as 2.3%.
The United States' $2 trillion economic relief package and the huge stimulus plans rolled out elsewhere have failed to ease worries about a severe economic damage due to the prolonged and intensified virus-containment measures.
"With the world going into quarantine, commodity prices have tanked, with risk assets also likely vulnerable this week as the virus continues to spread," ING economists Prakash Sakpal and Nicholas Mapa wrote in a note.
China's central bank unexpectedly cut the rate on reverse repurchase agreements by 20 basis points on Monday, the largest in nearly five years, as authorities stepped up measures to relieve pressure on an economy ravaged by the pandemic. about iron ore supply disruptions arising from lockdowns, which last week helped lift spot and futures prices, appeared to have eased somewhat, with miner Rio Tinto Ltd RIO.AX saying its Shanghai team would return to office as China recovers from the pandemic. Fortescue Metals Group FMG.AX said its mining, processing and shipping activities remained in line with its 2020 outlook. Australia's biggest iron ore miners are looking to reduce the threat to their operations from the pandemic, by pushing workers to spend weeks on site away from families and relocate from the eastern seaboard. Construction steel rebar on the Shanghai Futures Exchange SRBcv1 fell 1.9% while hot-rolled coil SHHCcv1 , used in cars and home appliances, slumped 1.6% and stainless steel SHSScv1 slipped 0.3%.>
* Coking coal DJMcv1 shed 0.4% while coke DCJcv1 lost 1.4%.
* Benchmark 62% iron ore for delivery to China SH-CCN-IRNOR62 settled at $87 a tonne on Friday, rebounding from a six-week low of $84.50 hit early last week, based on data from SteelHome consultancy.
($1 = 7.0962 yuan)