Manuka Resources (ASX:MKR) has secured firm commitments from institutional investors to raise AU$15 million via a share placement of around 200 million new shares at AU$0.075 each, representing a 9.8% discount to the five-day volume weighted average price, according to a Tuesday Australian bourse filing.

The placement will be conducted in two tranches, with around 34.4 million shares to be issued under tranche one within the company's existing placement capacity, and about 165.6 million shares under tranche two, which will be subject to shareholder approval, the filing said.

The funds will support upgrades and refurbishment at Wonawinta, exploration at Mt Boppy and Pipeline Ridge, and working capital, the filing added.