(Adds dateline, analyst comment in paragraph 8)

MELBOURNE, March 14 (Reuters) - Australia's Pilbara Minerals said on Thursday it has accepted a pre-auction offer for a shipment of 5,000 dry metric tonnes (dmt) of lithium spodumene concentrate cargo from a group of registered auction participants.

The shipment was made available for sale to a group of registered participants prior to the auction on Pilbara's Battery Metal Exchange (BMX), which had been scheduled for March 18, it said in an exchange filing.

Australia's biggest independent lithium miner has now allocated most of its supply for the year, it said, and future spot sales on the BMX exchange are unlikely.

Pilbara said on Tuesday it had inked a spodumene concentrate supply deal with Tesla supplier Sichuan Yahua Industrial Group, to be delivered from its Pilgangoora operation in Western Australia.

The lithium miner indicated that it received a number of offers prior to the auction and has accepted one and executed a sales contract with the buyer, whose name it did not disclose.

The lithium market has been stabilising after prices plunged more than 70% in 2023 on slower-than-expected sales growth of electric vehicles, as well as higher production and over-supply of the metal.

"The offer is good evidence and support of future demand and the pricing horizon," said analyst Tim Hoff of Canaccord in Perth.

The offer prices the shipment at $1,200 per dmt on a SC6.0 CIF China equivalent basis after adjusting for lithium content and including freight costs, Pilbara said.

The shipment is contracted for the December quarter given the firm already has existing offtake agreements with other parties. (Reporting by Megha Rani and Melanie Burton; Editing by Janane Venkatraman and Christopher Cushing)