June 11 (Reuters) - Activist investor Elliott Investment

Management said late on Wednesday that Australia's Northern Star

Resources ( NESRF ) must act immediately to restore shareholder

value by strengthening its board and undertaking a formal

strategic review.

Responding to a shareholder letter Northern Star released on

Wednesday, the U.S.-based investor said, "Board's letter

indicates that it does not understand the magnitude of change

required to win back shareholders' trust, starting with

significantly strengthening the board itself."

It said the case for a strategic review for Australia's

largest gold miner is now more apparent than it was before the

board published its letter.

Last week, Elliott disclosed an over A$1 billion ($699.30

million) stake in the gold miner and called for it to launch a

strategic review that would consider a sale, citing

underperformance versus peers.

($1 = 1.4300 Australian dollars)

(Reporting by Jasmeen Ara Shaikh in Bengaluru; Editing by

Subhranshu Sahu)