(Adds Granholm comments, changes dateline) U.S. Energy...

(Adds Granholm comments, changes dateline)

U.S. Energy Secretary Jennifer Granholm said the government is concerned that supplies of critical minerals, used widely in clean energy technology, could be subject to weaponisation as oil and gas have been amid the Ukraine conflict.

"Our concern is that critical minerals could be as subject or vulnerable to manipulation as we've seen in other areas, or weaponisation," Granholm said at the start of talks with Australia's resources minister and executives from 14 mining companies at the Sydney Energy Forum.

"I think it's healthy and from a national security perspective for both of our nations to diversify supply chains and make sure that these minerals are available to get to the ultimate goal of net zero," she said.

Companies at the meeting included global giant Rio Tinto (RIO) RIO.L , rare earths producer Lynas Rare Earths (LYC) , mineral sands miner Iluka Resources (ILU) , graphite miner Syrah Resources (SYR) and rare earths developer Arafura Resources (ARU) .

"We are very serious about establishing strong relationships with Australia and with you and with your potential customers for offtake," Granholm said.

Lynas recently won a $120 million contract from the U.S. defense department to build a heavy rare earths separation plant in Texas.