Nyrstar denies Trafigura influence after ousting chief executive

(Adds details, analyst comments)

By Philip Blenkinsop and Silvia Antonioli

BRUSSELS/LONDON, Nov 26 (Reuters) - Zinc producer Nyrstar SA has ousted its chief executive and is replacing him temporarily with its finance chief, a surprise change only weeks after commodities trader Trafigura bought a large stake in the company.

Nyrstar (Brussels: NYR.BR - news) said Roland Junck, 59, had left to pursue other interests after nearly six years in the post and Chief Financial Officer Heinz Eigner had been appointed acting CEO while the board seeks a permanent replacement.

It said Trafigura had no bearing on the move. "The board decided that it was time to choose a new leader. It was a mutual agreement between the board and Mr. Junck," said Nyrstar spokesman Greg Morsbach. Trafigura declined comment.

However market sources told Reuters last month Trafigura was aiming to influence board decisions and tighten its grip on the world's largest zinc producer.

"Junck's seemingly abrupt departure ... may raise suspicions that his decision to step down at this time was no coincidence," said analyst Alon Olsha at brokerage Macquarie. "One can also only speculate whether Trafigura used their leverage to effect this change."

Trafigura started in September to build a stake which stands at at least 15 percent, making it the company's largest shareholder.

Analysts said Junck's track record at the helm Nyrstar had been disappointing, arguing his strategy to invest in buying mines in particular was poorly executed and failed to achieve its stated objective on production or costs.

"The management change could possibly bring a bit more enthusiasm in the investor community, depending on who is named as the permanent CEO ... it could be a net positive for the group," said Citi analysts in a note.

Nyrstar has since September raised 600 million euros ($748 million) with a bond yielding 9 percent and a share issue to transform its site in Port Pirie, Australia and to upgrade its smelters.

The company, formed from merging the zinc smelting businesses of Belgium's Umicore and Australia's Zinifex, floated in 2007 at 20 euros per share, but it languishes well below that level and closed on Tuesday at 2.74 euros, weighed down by a low zinc price, investor impatience with its mining expansion and the failure of its Finnish supplier Talvivaara, which earlier this month applied for bankruptcy.

Trafigura has already tried to influence the composition of the board of another company in which it invested. After building an 18 percent stake in EMED Mining it proposed last month to oust all but one of its directors and substitute them with its own nominees. (1 US dollar = 0.8021 euros) (Editing by Greg Mahlich and David Holmes)