Mining investment company Zambia Copper Investments Ltd (ZCIJ.J: Quote) confirmed on Friday it had made a binding $22.5 million offer for exploration and development company African Copper (ACU.L: Quote).

Zambia Copper, which until last year owned 65 percent of the Konkola Copper Mine in Zambia, said it was looking to invest in African-based mining companies.

The bid, which would see Zambia Copper take a 69.7 percent stake in African Copper, rivals a $15 million offer made by mining investment firm Natasa Mining Ltd (NSN.L: Quote) on 16 March.

Shares in African Copper, which is tri-listed in London, Toronto and Botswana, jumped 10 percent to stand at 2.6 pence at 0744 GMT on London's junior AIM market.

The total financing package of around $22.5 million includes a subscription for 677 million shares at 1 pence per share and a four year secured convertible credit facility.

It also includes a loan of $2.5 million to meet African Copper's immediate working capital needs and enable it to repay $1.5 million in financing it was advanced by Natasa last month.

The Natasa loan was to be repaid through a proposed $6.5 million equity placement -- which would give Natasa ownership of 70 percent of the company -- as well as a proposed $8.5 million debt facility.

Under the agreement, African Copper provided Natasa with the right of exclusivity, preventing it from entering into discussions with any other party in relation to any corporate transaction until 15 May 2009.

African Copper, which is involved in the exploration and development of copper deposits in Botswana, said on Thursday it had received an unsolicited offer of finance from Zambia Copper but did not intend to respond to it before its planned extraordinary general meeting on May 7.

Zambia Copper said its offer remains open for acceptance by African Copper at any time before 20 May 2009.

(Reporting by Kylie MacLellan; Editing by Rosalba O'Brien)

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