An ASX-listed critical minerals hopeful backed by the Trump administration has halted trading in its shares after an American activist investor alleged there were inaccuracies in its accounts and questioned whether it could commercialise its technology.

North Carolina-based IperionX is developing titanium extraction technology and has been among the winners of a White House push to secure domestic production of critical minerals, receiving $US47 million ($71 million) from the Defence Department to accelerate production. The metal has many military uses, including in the construction of aircraft and warships.