Gold and copper miner Freeport-McMoRan (FCX 0.52%) will pay its shareholders a supplemental dividend of $1.00 per share upon the completion of its acquisition of Plains Exploration & Production (NYSE: PXP), the company announced today. The supplemental payout will be in addition to the miner's regular quarterly dividend of $0.3125 per share.

Plains Exploration shareholders are set to vote on the $6.9 billion cash and stock deal today.

Additionally, Freeport's board of directors said they would pay to shareholders of Plains Exploration a $3.00-per-share cash dividend upon completion of the transaction.

Freeport Chairman James R. Moffett and President and CEO Richard C. Adkerson said in a joint statement:  "This dividend in no way changes our commitment to reduce debt on completion of the pending acquisitions. The planned asset sales, combined with our significant cash flows and disciplined approach to investing in capital projects, will enable us to meet our target of reducing debt to $12 billion over a three year period."

Assuming the acquisition is completed, Freeport plans to also complete $1.5 billion in asset sales from the combined company as a means of reducing its capital spending plans.

The supplemental dividend, which is conditional on the closing of the transaction, will cost Freeport $1 billion and will be the 11th supplemental dividend paid since 2004.

link