LUSAKA, Sept 4 (Reuters) - Zambia's Mopani Copper Mines' output declined in the first-half of this year contributing to deeper losses at the operation bought from Glencore in 2021.

Mopani's losses worsened to $196 million in the six months through June, compared to $120 million in the prior period, as output dropped and costs rose, parent company ZCCM-IH said in a statement. Copper output during the period declined to 14,946 tons from 20,000 tons in the same period last year.

The loss is a further blow to the company's finances after it suffered a $298 million loss last year compared to $74.2 million in 2021.

Zambia's state-owned ZCCM took control of Mopani from Glencore in 2021 after agreeing to pay the Swiss mining giant $1.5 billion in a deal funded by debt.

Since then, ZCCM has been searching for a new investor to take over the Mopani assets. A process to sell the mines is being managed by Rothschild & Co and could be completed by December, ZCCM said.

The new investor is expected to invest in completing projects that Glencore had been working on that could raise copper output to about 200,000 tons per year by 2027.

Rothschild has narrowed the list of Mopani's potential buyers to Sibanye Stillwater and Zijin Mining Group.

Mopani requires $300 million investment to expand output over the next three years and an additional $150 million to sustain operations, ZCCM said. (Reporting by Chris Mfula; Editing by Felix Njini and Sharon Singleton)