Panoramic Resources has unanimously recommended shareholders reject a $312 million takeover offer by larger peer Independence Group.
The ASX-listed nickel miner said in a statement the offer was "opportunistically timed" and shareholders would reduce their exposure to "near-term improvements in operational performance" if they accepted.
Shareholders also should wait to see if a superior offer emerged, it added.
Independence made the bid on November 4, offering one IGO share for every 13 Panaromic shares held, with an implied offer price of 47.6 cents per Panoramic share.
Panoramic on Thursday also announced a 1 for 6 accelerated pro-rata non-renounceable entitlement offer to raise about $31 million after costs.
Independence restated last month that any capital-raising offer by Panoramic would represent a breach of their offer.